Add a new filter option to [GithubCommitActivity], allowing users to filter the commit activity by a specific author.

To make the filter more explicit, The label display "commits by [author]" for the total amount of commits and "commit activity by [author]" for other intervals when an author filter is selected.

To maintain a clear and organized code structure, The filtered author is added as an argument and not to the shield path.

The request to find the number of commits by the author is made using the REST api rather then the GraphQL api to make it in 1 request rather then 2.

Resolves badges#9215

Add tests for the new filter by author feature.

Add test for new transformAuthorFilter function of GithubCommitActivity added for the author filter feature.

The author filter error handling removed was redundent as it would never execute, there is no way to seperate branch not found from repo not found.

PR badges#9233 replaced errorsMessages with httpErrors.
This commit updates the new changes to stay up to date with that PR

this exception was removed in commit 9e358c8 and is not needed anymore

Picked a user with commits in the repo as an example that would work

Add test for REST API calls in commit activity branch