Bump actions/setup-python from 6 to 7 (#126)

Bumps [actions/setup-python](https://github.com/actions/setup-python) from 6 to 7.
- [Release notes](https://github.com/actions/setup-python/releases)
- [Commits](actions/setup-python@v6...v7)

---
updated-dependencies:
- dependency-name: actions/setup-python
  dependency-version: '7'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

.github/workflows/ci.yml

@@ -25,7 +25,7 @@ jobs:
       CFLAGS: ${{ matrix.config.cflags }}
     steps:
       - uses: actions/checkout@v7
-      - uses: actions/setup-python@v6
+      - uses: actions/setup-python@v7
       - name: Dependencies (ubuntu)
         if: contains(matrix.os, 'ubuntu')
         run: sudo apt update && sudo apt install -y gifsicle valgrind meson