[Backport 2.19] Preserve user when stashing thread context when sending alert notification messages. #2027

[AWSHurneyt]

Description

Manual backport of PR #2027

Related Issues

Resolves #[Issue number to be closed when this PR is merged]

Check List

• New functionality includes testing.
• New functionality has been documented.
• API changes companion pull request created.
• Commits are signed per the DCO using --signoff.
• Public documentation issue/PR created.

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[AWSHurneyt]

The Security Test Workflow / Build and test Alerting workflows are failing because the security plugin is failing to initialize which is preventing the cluster from starting. This issue isn't related to the changes in this PR.
https://github.com/opensearch-project/alerting/actions/runs/22608902503/job/65507079411?pr=2030#step:7:125

][o.o.s.OpenSearchSecurityPlugin] [b3168d08a704] OpenSearch Config path is /usr/share/opensearch/config
Error: 3-03T04:56:12,213][ERROR][o.o.b.OpenSearchUncaughtExceptionHandler] [b3168d08a704] uncaught exception in thread [main]
org.opensearch.bootstrap.StartupException: java.lang.IllegalStateException: failed to load plugin class [org.opensearch.security.OpenSearchSecurityPlugin]
	at org.opensearch.bootstrap.OpenSearch.init(OpenSearch.java:185)
	at org.opensearch.bootstrap.OpenSearch.execute(OpenSearch.java:172)
	at org.opensearch.cli.EnvironmentAwareCommand.execute(EnvironmentAwareCommand.java:104)
	at org.opensearch.cli.Command.mainWithoutErrorHandling(Command.java:138)
	at org.opensearch.cli.Command.main(Command.java:101)
	at org.opensearch.bootstrap.OpenSearch.main(OpenSearch.java:138)
	at org.opensearch.bootstrap.OpenSearch.main(OpenSearch.java:104)
Caused by: java.lang.IllegalStateException: failed to load plugin class [org.opensearch.security.OpenSearchSecurityPlugin]
	at org.opensearch.plugins.PluginsService.loadPlugin(PluginsService.java:818)
	at org.opensearch.plugins.PluginsService.loadBundle(PluginsService.java:757)
	at org.opensearch.plugins.PluginsService.loadBundles(PluginsService.java:551)
	at org.opensearch.plugins.PluginsService.<init>(PluginsService.java:197)
	at org.opensearch.node.Node.<init>(Node.java:524)
	at org.opensearch.node.Node.<init>(Node.java:451)
	at org.opensearch.bootstrap.Bootstrap$5.<init>(Bootstrap.java:242)
	at org.opensearch.bootstrap.Bootstrap.setup(Bootstrap.java:242)
	at org.opensearch.bootstrap.Bootstrap.init(Bootstrap.java:404)
	at org.opensearch.bootstrap.OpenSearch.init(OpenSearch.java:181)
	... 6 more
Caused by: java.lang.reflect.InvocationTargetException
	at java.base/jdk.internal.reflect.DirectConstructorHandleAccessor.newInstance(DirectConstructorHandleAccessor.java:74)
	at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:502)
	at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:486)
	at org.opensearch.plugins.PluginsService.loadPlugin(PluginsService.java:809)
	... 15 more
Caused by: java.util.ServiceConfigurationError: java.util.spi.CalendarDataProvider: Provider org.opensearch.common.time.IsoCalendarDataProvider could not be instantiated
	at java.base/java.util.ServiceLoader.fail(ServiceLoader.java:586)
	at java.base/java.util.ServiceLoader$ProviderImpl.newInstance(ServiceLoader.java:813)
	at java.base/java.util.ServiceLoader$ProviderImpl.get(ServiceLoader.java:729)
	at java.base/java.util.ServiceLoader$3.next(ServiceLoader.java:1403)
	at java.base/sun.util.locale.provider.SPILocaleProviderAdapter$1.run(SPILocaleProviderAdapter.java:83)
	at java.base/sun.util.locale.provider.SPILocaleProviderAdapter$1.run(SPILocaleProviderAdapter.java:76)
	at java.base/java.security.AccessController.doPrivileged(AccessController.java:571)
	at java.base/sun.util.locale.provider.SPILocaleProviderAdapter.findInstalledProvider(SPILocaleProviderAdapter.java:76)
	at java.base/sun.util.locale.provider.AuxLocaleProviderAdapter.getLocaleServiceProvider(AuxLocaleProviderAdapter.java:73)
	at java.base/sun.util.locale.provider.LocaleServiceProviderPool.findProviders(LocaleServiceProviderPool.java:313)
	at java.base/sun.util.locale.provider.LocaleServiceProviderPool.getLocalizedObjectImpl(LocaleServiceProviderPool.java:283)
	at java.base/sun.util.locale.provider.LocaleServiceProviderPool.getLocalizedObject(LocaleServiceProviderPool.java:265)
	at java.base/sun.util.locale.provider.CalendarDataUtility.retrieveFirstDayOfWeek(CalendarDataUtility.java:76)
	at java.base/java.util.Calendar.setWeekCountData(Calendar.java:3413)
	at java.base/java.util.Calendar.<init>(Calendar.java:1612)
	at java.base/java.util.GregorianCalendar.<init>(GregorianCalendar.java:741)
	at java.base/java.util.Calendar$Builder.build(Calendar.java:1497)
	at java.base/sun.util.locale.provider.CalendarProviderImpl.getInstance(CalendarProviderImpl.java:87)
	at java.base/java.util.Calendar.createCalendar(Calendar.java:1700)
	at java.base/java.util.Calendar.getInstance(Calendar.java:1663)
	at java.base/java.text.SimpleDateFormat.initializeCalendar(SimpleDateFormat.java:680)
	at java.base/java.text.SimpleDateFormat.<init>(SimpleDateFormat.java:624)
	at com.fasterxml.jackson.databind.util.StdDateFormat.<clinit>(StdDateFormat.java:116)
	at com.fasterxml.jackson.databind.ObjectMapper.<clinit>(ObjectMapper.java:411)
	at org.opensearch.security.DefaultObjectMapper.<clinit>(DefaultObjectMapper.java:81)
	at org.opensearch.security.ssl.OpenSearchSecuritySSLPlugin.<init>(OpenSearchSecuritySSLPlugin.java:227)
	at org.opensearch.security.OpenSearchSecurityPlugin.<init>(OpenSearchSecurityPlugin.java:326)
	at java.base/jdk.internal.reflect.DirectConstructorHandleAccessor.newInstance(DirectConstructorHandleAccessor.java:62)
	... 18 more
Caused by: java.security.AccessControlException: access denied ("java.lang.RuntimePermission" "localeServiceProvider")
	at java.base/java.security.AccessControlContext.checkPermission(AccessControlContext.java:488)
	at java.base/java.security.AccessController.checkPermission(AccessController.java:1071)
	at java.base/java.lang.SecurityManager.checkPermission(SecurityManager.java:411)
	at java.base/java.util.spi.LocaleServiceProvider.checkPermission(LocaleServiceProvider.java:161)
	at java.base/java.util.spi.LocaleServiceProvider.<init>(LocaleServiceProvider.java:175)
	at java.base/java.util.spi.CalendarDataProvider.<init>(CalendarDataProvider.java:45)
	at org.opensearch.common.time.IsoCalendarDataProvider.<init>(IsoCalendarDataProvider.java:47)
	at java.base/jdk.internal.reflect.DirectConstructorHandleAccessor.newInstance(DirectConstructorHandleAccessor.java:62)
	at java.base/java.lang.reflect.Constructor.newInstanceWithCaller(Constructor.java:502)
	at java.base/java.lang.reflect.Constructor.newInstance(Constructor.java:486)
	at java.base/java.util.ServiceLoader$ProviderImpl$2.run(ServiceLoader.java:797)
	at java.base/java.security.AccessController.doPrivileged(AccessController.java:714)
	at java.base/java.util.ServiceLoader$ProviderImpl.newInstance(ServiceLoader.java:802)
	... 44 more
Error: Process completed with exit code 1.