Allow comparison with a commit different from last one

[RemiBardon]

From the beginning, we made sure the program isn't blocked to comparing a file only with its last revision. Our script takes two commit hashes, and this allows reusability for a 1 commit to N commits comparison. Another idea was to allow a comparison with the last minor/major release, which would be possible.

To make it configurable, we'd like to add a "compare_with" option to the GitHub Action which would accept:

• (last commit: Compare every changed file with last commit (same result as last-revision))
• last revision or nothing: Compare every changed file with their last revision
• average of [N] revisions: Compare every changed file with their N last revisions (making an average of past results)
• last patch: Compare every changed file with their version in the last patch release (X.X.N)
• last minor: Compare every changed file with their version in the last minor release (X.N.X)
• last major: Compare every changed file with their version in the last major release (N.X.X)
• Anything else: Treated as a commit hash → Compare every changed file with their version at the given hash

The problem is: there is no relationship between a commit hash in the choco-solver repo and this one. Same goes for releases.