test(meson): fix SSLClientServerTest.* tests with OpenSSL 3.2.0

Since OpenSSL commit
<openssl/openssl@342e365>,
the default X.509 certificate format generated with the `openssl req`
command has been changed to X.509 v3 from X.509 v1.

For some reason, this change breaks cpp-httplib's SSLClientServerTest.*
tests.

To fix the test failures, this patch passes the '-x509v1' flag instead
of '-x509' when OpenSSL 3.2.0 or newer is detected. To detect the
version of a command line utility, Meson 0.62.0 or later is required.

Fixes <#1798>, but only for
the Meson build system.

test/meson.build

@@ -6,6 +6,7 @@ gtest_dep = dependency('gtest', main: true)
 libcurl_dep = dependency('libcurl')
 openssl = find_program('openssl')
 test_conf = files('test.conf')
+req_x509_flag = openssl.version().version_compare('>=3.2.0') ? '-x509v1' : '-x509'
 
 key_pem = custom_target(
   'key_pem',
@@ -31,7 +32,7 @@ cert2_pem = custom_target(
   'cert2_pem',
   input: key_pem,
   output: 'cert2.pem',
-  command: [openssl, 'req', '-x509', '-config', test_conf, '-key', '@INPUT@', '-sha256', '-days', '3650', '-nodes', '-out', '@OUTPUT@', '-extensions', 'SAN']
+  command: [openssl, 'req', req_x509_flag, '-config', test_conf, '-key', '@INPUT@', '-sha256', '-days', '3650', '-nodes', '-out', '@OUTPUT@', '-extensions', 'SAN']
 )
 
 key_encrypted_pem = custom_target(
@@ -44,7 +45,7 @@ cert_encrypted_pem = custom_target(
   'cert_encrypted_pem',
   input: key_encrypted_pem,
   output: 'cert_encrypted.pem',
-  command: [openssl, 'req', '-x509', '-config', test_conf, '-key', '@INPUT@', '-sha256', '-days', '3650', '-nodes', '-out', '@OUTPUT@', '-extensions', 'SAN']
+  command: [openssl, 'req', req_x509_flag, '-config', test_conf, '-key', '@INPUT@', '-sha256', '-days', '3650', '-nodes', '-out', '@OUTPUT@', '-extensions', 'SAN']
 )
 
 rootca_key_pem = custom_target(
@@ -57,7 +58,7 @@ rootca_cert_pem = custom_target(
   'rootca_cert_pem',
   input: rootca_key_pem,
   output: 'rootCA.cert.pem',
-  command: [openssl, 'req', '-x509', '-new', '-batch', '-config', files('test.rootCA.conf'), '-key', '@INPUT@', '-days', '1024', '-out', '@OUTPUT@']
+  command: [openssl, 'req', req_x509_flag, '-new', '-batch', '-config', files('test.rootCA.conf'), '-key', '@INPUT@', '-days', '1024', '-out', '@OUTPUT@']
 )
 
 client_key_pem = custom_target(