scheduleBuild() uses the deprecated LegacyCodeCause

[jglick]

Led to junk in indexing.xml like this:

<?xml version='1.0' encoding='UTF-8'?>
<jenkins.branch.MultiBranchProject_-BranchIndexing plugin="[email protected]">
  <actions>
    <hudson.model.CauseAction>
      <causes>
        <hudson.model.Cause_-LegacyCodeCause>
          <stackTrace>
            <trace>hudson.model.Cause$LegacyCodeCause.&lt;init&gt;(Cause.java:130)</trace>
            <trace>jenkins.branch.MultiBranchProject.scheduleBuild(MultiBranchProject.java:2002)</trace>
            …
          </stackTrace>
        </hudson.model.Cause_-LegacyCodeCause>
      </causes>
    </hudson.model.CauseAction>
  </actions>
  …
</jenkins.branch.MultiBranchProject_-BranchIndexing>

@reviewbybees esp. @stephenc

[ghost]

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[jenkinsadmin]

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[oleg-nenashev]

🐝
Not important: Would be 🐝 😄 if Javadocs of deprecated methods refer the right ones

[tfennelly]

🐝

[jglick]

I guess you can figure out that the method has non-deprecated overloads. :-)

[jglick]

@reviewbybees done

[ghost]

This pull request has completed our internal processes and we now respectfully request the maintainers of this repository to consider our proposal contained within this pull request for merging.