feat: Add GitHub Actions workflow to find the smallest supported Rust version

[derrix060]

The idea of this workflow is to ensure we have up-to-date documentation on the minimum required version of rust. It will only run on PRs that touch either this workflow or rust files

Since there is no easy way to have a workflow to be required and only run on some cases, it will send a message to the PR every time the minimum version changes

[codecov[bot]]

Codecov Report

All modified and coverable lines are covered by tests :white_check_mark:

Project coverage is 78.44%. Comparing base (153e651) to head (ced3f65).

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #2145 +/- ## ========================================== - Coverage 78.46% 78.44% -0.03% ========================================== Files 100 100 Lines 9221 9221 ========================================== - Hits 7235 7233 -2 - Misses 1351 1352 +1 - Partials 635 636 +1 ```

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