JENKINS-73658 Support regex for tag filter

[camjcorley]

This PR adds logic to allow for a regex filter to be used for the tagFilter. The changes include:

• Add this new option to the parameter description displayed in Jenkins.
• If the tagFilter supplied starts with a forward slash ('/') it is assumed to be a regex pattern. As a result, the git client call for tags will use an asterisk instead of the tagFilter (pulling all tag names).
• If we're using a regex pattern, only tags that match will be included.

Testing done

In a local instance of Jenkins, installed the plugin and ensured the following patterns functioned as desired:

• No filter ('').
• A plain text filter ('dev').
• A wildcard text filter ('staging*').
• A regex pattern filter ('/.(dev|staging).').

Submitter checklist

• Make sure you are opening from a topic/feature/bugfix branch (right side) and not your main branch!
• Ensure that the pull request title represents the desired changelog entry
• Please describe what you did
• Link to relevant issues in GitHub or Jira: https://issues.jenkins.io/browse/JENKINS-73658
• Link to relevant pull requests, esp. upstream and downstream changes
• Ensure you have provided tests - that demonstrates feature works or fixes the issue

[camjcorley]

Let me know if you have any feedback or would like this implemented differently. Thanks!

[camjcorley]

@jenkinsadmin @MarkEWaite sorry for the direct ping, this PR has been open for a few months now and I'm hoping to get a review. My team relies on this modification and it would be great to get it into the plugin repository to simplify upgrades to our jenkins instance. Thanks!

[camjcorley]

@jenkinsadmin @MarkEWaite sorry for the direct ping, this PR has been open for a few months now and I'm hoping to get a review. My team relies on this modification and it would be great to get it into the plugin repository to simplify upgrades to our jenkins instance. Thanks!

Looks like a Windows test is failing after I synced my branch with master, possibly due to an Azure outage I see on the jenkinsci jenkins?

[MarkEWaite]

I would very much like to have one or more tests that confirm the added functionality is working as expected. I'd also like to have additional text added to the README file that describes the added functionality.