Require Jenkins 2.426.3 or newer

[MarkEWaite]

Require Jenkins 2.426.3 or newer

Plugin installation statistics show that 80% of the installations of 787.v665fcf2a_830b_ (6 months old) are already running Jenkins 2.426.3.

SECURITY-3314 advises users to upgrade to Jenkins 2.426.3 or newer to resolve a critical security vulnerability.

This will need to be merged if the experimental upgrade of the promoted builds optional dependency is successful. Refer to:

• Bump promoted-builds optional dependency to 892.vd6219fc0a_efb #378

Testing done

Relying on ci.jenkins.io to run the tests. Tests pass for:

• Bump org.jenkins-ci.plugins:promoted-builds from 3.11 to 945.v597f5c6a_d3fd #377

Submitter checklist

Beta Give feedback

1. Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
2. Ensure that the pull request title represents the desired changelog entry
3. Please describe what you did
4. Link to relevant issues in GitHub or Jira
5. Link to relevant pull requests, esp. upstream and downstream changes
6. Ensure you have provided tests - that demonstrates feature works or fixes the issue

[MarkEWaite]

Tests pass in the plugin BOM when the optional dependency on promoted builds plugin is updated to the same new value in both the git plugin and the parameterized trigger plugin. That means we'll need a release of git plugin and a release of parameterized trigger plugin in the same plugin BOM release.