Bump actions/cache from 5 to 6

Bumps [actions/cache](https://github.com/actions/cache) from 5 to 6.
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v5...v6)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-version: '6'
  dependency-type: direct:production
  update-type: version-update:semver-major
...

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

Author: dependabot[bot]

.github/workflows/build.yml

@@ -41,7 +41,7 @@ jobs:
 
     - name: Cache sccache (Windows)
       if: runner.os == 'Windows'
-      uses: actions/cache@v5
+      uses: actions/cache@v6
       with:
         path: C:\Users\runneradmin\AppData\Local\sccache
         key: sccache-${{ runner.os }}-${{ github.sha }}
@@ -50,7 +50,7 @@ jobs:
 
     - name: Cache pip (Windows)
       if: runner.os == 'Windows'
-      uses: actions/cache@v5
+      uses: actions/cache@v6
       with:
         path: C:\Users\runneradmin\AppData\Local\pip\Cache
         key: pip-${{ runner.os }}-${{ hashFiles('pyproject.toml') }}