Apply Push rules commit messages restriction to protected branches only
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Currently, the Push rules commit messages restriction feature works globally across all branches.
Is it not possible to restrict only some branches (probably protected branches).
### Problem to solve
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As Rachel (Release Manager), I would like all the commits in the protected ("main") branches to contain the relevant JIRA issues.
As Sasha (Software Developer), I would like to commit changes to non-protected branches (work/dev branches) without any restriction.
### Intended users
* [Sasha (Software Developer)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#sasha-software-developer)
* [Devon (DevOps Engineer)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#devon-devops-engineer)
* [Rachel (Release Manager)](https://about.gitlab.com/handbook/marketing/product-marketing/roles-personas/#rachel-release-manager)
### User experience goal
The user should be able to push any commit messages to non-protected branches.
The user should not be able to push non-compliant commit messages to protected branches.
### Proposal
Limit the commit messages restriction to specific branches, either by name or by type (protected/not protected branches).
### What is the type of buyer?
This should be at least Starter tier, as the whole push restrictions are at this tier. This might as well be locked to Premium users.
issue