feat: Add total commits to [GitHubCommitActivity] (#9196)

* feat: Add total commits to GithubCommitActivity

As part of a new feature proposed at issue #6070 added the requested feature.
I also used the conversation at pull request #6081 as a basis for those changes.

This change adds a new interval to the github/commit-activity shield 'total' (t for short).
The interval shows the total commits of the repo since its creation.

* Fix format with prettier

* Label for 'total' interval is now commits

Label change for the 'total' interval from 'commit activity' to 'commits'

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Co-authored-by: jNullj <jNullj@users.noreply.github.com>
Co-authored-by: repo-ranger[bot] <39074581+repo-ranger[bot]@users.noreply.github.com>