Remove `useBeta` property from `pom.xml`

[strangelookingnerd]

Now that the permission Jenkins.MANAGE is out of beta (https://github.com/jenkinsci/jenkins/pull/10183) the useBeta property is no longer required.

This is still a draft, since it will take some time until that change is shipped in an LTS and this plugin updates to it. I would like to use this PR as a reminder and update / merge it once the requirements are met.

Testing done

Validated with mvn clean verify

Submitter checklist

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

[strangelookingnerd]

The required change in the Jenkins core (https://github.com/jenkinsci/jenkins/pull/10183) was shipped with the latest LTS 2.504.1. While there is no urgency to merge this PR, it should not get burried either 👍🏼

[MarkEWaite]

The required change in the Jenkins core (jenkinsci/jenkins#10183) was shipped with the latest LTS 2.504.1. While there is no urgency to merge this PR, it should not get burried either 👍🏼

I don't plan to require Jenkins 2.504.1 as minimum Jenkins version for several months at least. I'll keep this in mind once Jenkins 2.504.1 becomes the minimum Jenkins version required by the plugin.