[FIXED JENKINS-22142] Removed obsolete method.

Hoping nobody uses it programmatically. Also, added `@Restricted` to the new one.

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Fixes an issue introduced in PR #1124: Stapler will happily select action methods that have no chance to execute successfully due to missing parameter annotations. While this behavior might be changed in the future (removing action methods can be dangerous, see e.g. https://github.com/jenkinsci/jenkins/commit/f97b5b33b0754532b945340cdee4b6ea1d2f6ba4#commitcomment-5946853), right now, removing it seems to be the only way to resolve the issue.