chore(deps): 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] <[email protected]>

Author: dependabot[bot]

.github/workflows/build.yml

@@ -25,7 +25,7 @@ jobs:
       run: pip install conan
 
     - name: Load Conan cache
-      uses: actions/cache@v5
+      uses: actions/cache@v6
       with:
         path: ~/.conan2/p
         key: Conan-${{ hashFiles('src/**/conanfile.txt') }}-${{ matrix.compiler }}-${{ matrix.platform }}