New command `Dependabot revert`

### Is there an existing issue for this?

- [X] I have searched the existing issues

### Feature description

In https://github.com/FreeTubeApp/FreeTube/pull/3758 we updated this dependency but we noticed that it wasn't working properly and had to revert in https://github.com/FreeTubeApp/FreeTube/pull/3761.

The problem is that one of the maintainers of our repo created the PR to revert it and that means we have one person less to review a PR. We have a small team and one person less to review a PR is a big deal because we need at least 3 people to approve it.

So as a solution to this issue i thought: What if i just could give the command `Dependabot revert` on https://github.com/FreeTubeApp/FreeTube/pull/3758 and it would create a PR reverting the change it made. That way the Dependabot creates the PR and free up a review spot because we dont have to create a PR for it.

I know u can make the argument that this is more an issue on our end then yours but i would to like to know what u think of adding this option.

Start by reviewing the feature description and the referenced PRs #3758 and #3761 to understand the dependency change and its revert. Define how a `Dependabot revert` command would identify the original change and create a reverting pull request; done means the behavior and required implementation scope are specified and covered by appropriate tests.

Written by the indexing model from the issue text.