chore(github): create PRs for nix flake updates automatically

[ch4og]

Description of change

Automatically creates PR with flake.lock update, which is file with Nix dependencies It doesn't run it on PRs not to create PRs from PRs

How has this been tested? (if applicable)

Here is action run https://github.com/thingsbych/binsider/actions/runs/11388924732/job/31687028064 And PR that it created https://github.com/thingsbych/binsider/pull/3

[codecov[bot]]

Codecov Report

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

Project coverage is 3.31%. Comparing base (03de375) to head (2f125ec). Report is 2 commits behind head on main.

Additional details and impacted files

```diff @@ Coverage Diff @@ ## main #85 +/- ## ===================================== Coverage 3.31% 3.31% ===================================== Files 19 19 Lines 2417 2417 ===================================== Hits 80 80 Misses 2337 2337 ```

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[orhun]

I don't get why we need this. Can we maybe run it weekly like we do with Dependabot? Can you explain it a bit?

[ch4og]

Sadly dependabot can't update nix flakes (https://github.com/dependabot/dependabot-core/issues/7340), but ofc it can be ran weekly

EDIT: At first I misread your comment 😅

[ch4og]

Moved it from CI and set cron to weekly