Hide delete branch button when user doesn't have permission

What does this MR do and why?

Contributes to #375225 (closed)

Verify user's permissions and hide branch delete button if needed.

Screenshots or screen recordings

Reporter user

Before	After

How to set up and validate locally

1. Create a project and add a member with Reporter access level there
2. Create a new branch in this project
3. Sign in as Reporter, go to Repository > Branches

MR acceptance checklist

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• I have evaluated the MR acceptance checklist for this MR.