WIP: Add author restriction push rule

What does this MR do?

The committer restriction push rule can be used to ensure that every commit that is pushed was commited by the same user. However, the author may be any other user. This could be misleading if the author was maliciously set to another user.

This new push rule allows project maintainers and instance admins to require the commit author email to be the same as the user pushing the commit in the same way that the committer restriction requires the commit comitter email to be the same as the user pushing the commit.

Closes #34374 (closed)

Screenshots

Does this MR meet the acceptance criteria?

Conformity

• Changelog entry
• Documentation (if required)
• Code review guidelines
• Merge request performance guidelines
• Style guides
• Database guides
• Separation of EE specific content

Availability and Testing

• Review and add/update tests for this feature/bug. Consider all test levels. See the Test Planning Process.
• Tested in all supported browsers

Security

If this MR contains changes to processing or storing of credentials or tokens, authorization and authentication methods and other items described in the security review guidelines:

• Label as security and @ mention @gitlab-com/gl-security/appsec
• The MR includes necessary changes to maintain consistency between UI, API, email, or other methods
• Security reports checked/validated by a reviewer from the AppSec team