Remove dependency to deprecated Extended Choice Parameter Plugin

### What feature do you want to see added?

[_Extended Choice Parameter Plugin_](https://plugins.jenkins.io/extended-choice-parameter) has been deprecated by jenkins but it cannot be uninstalled due to _**Custom Tools plugin**_ [dependency](https://github.com/jenkinsci/custom-tools-plugin/blob/27beb098cac7886f7b74d06cd61da47ca5ed733a/pom.xml#L65).

As it's currently not possible to "hide" the deprecation message from the jenkins UI, it makes this a hard to ignore matter 😅

Would it be possible to have the _Custom Tools plugin_'s logic updated to break the dependency on [_Extended Choice Parameter Plugin_](https://plugins.jenkins.io/extended-choice-parameter) so this can be uninstalled while preserving _Custom Tools plugin_?

Thanks!

### Upstream changes

_No response_

### Are you interested in contributing this feature?

_No response_

Start with the dependency declaration in pom.xml linked by the issue, then trace how the Extended Choice Parameter Plugin is used by the Custom Tools plugin. Update the dependency and related logic so the plugin still builds and works while Extended Choice Parameter Plugin can be uninstalled; verify the repository tests and build.

Written by the indexing model from the issue text.