ci: bump actions/checkout from 6.0.1 to 6.0.2

Bumps [actions/checkout](https://github.com/actions/checkout) from 6.0.1 to 6.0.2.
- [Release notes](https://github.com/actions/checkout/releases)
- [Changelog](https://github.com/actions/checkout/blob/main/CHANGELOG.md)
- [Commits](actions/checkout@8e8c483...de0fac2)

---
updated-dependencies:
- dependency-name: actions/checkout
  dependency-version: 6.0.2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

Author: dependabot[bot]

.github/workflows/main.yml

@@ -7,7 +7,7 @@ jobs:
       rel0: ${{ steps.query.outputs.rel0 }}
     steps:
       - name: Checkout
-        uses: actions/checkout@8e8c483db84b4bee98b60c0593521ed34d9990e8 # v4
+        uses: actions/checkout@de0fac2e4500dabe0009e67214ff5f5447ce83dd # v4
         with:
           submodules: recursive
       - name: Query PyPI for recent PySide release number