chore(deps): bump actions/cache

Bumps the actions group in /.github/actions/prepare-build-env with 1 update: [actions/cache](https://github.com/actions/cache).


Updates `actions/cache` from 4.1.2 to 4.2.0
- [Release notes](https://github.com/actions/cache/releases)
- [Changelog](https://github.com/actions/cache/blob/main/RELEASES.md)
- [Commits](actions/cache@v4.1.2...v4.2.0)

---
updated-dependencies:
- dependency-name: actions/cache
  dependency-type: direct:production
  update-type: version-update:semver-minor
  dependency-group: actions
...

Signed-off-by: dependabot[bot] <[email protected]>

.github/actions/prepare-build-env/action.yml

@@ -22,7 +22,7 @@ runs:
 
     - name: Cache rust-toolchain (restore)
       id: rustup-cache
-      uses: actions/cache/restore@v4.1.2
+      uses: actions/cache/restore@v4.2.0
       with:
        path: |
          ~/.rustup/toolchains
@@ -45,7 +45,7 @@ runs:
         echo "version=$(rustc --version | cut -d ' ' -f 2)" >> $GITHUB_OUTPUT
 
     - name: Cache rust-toolchain (save)
-      uses: actions/cache/save@v4.1.2
+      uses: actions/cache/save@v4.2.0
       if: steps.rustup-cache.outputs.cache-hit != 'true' && (github.ref == 'refs/heads/main' || github.ref == 'refs/heads/develop')
       with:
         path: |
@@ -56,7 +56,7 @@ runs:
 
     - name: Cache cargo output (restore)
       id: cargo-cache
-      uses: actions/cache/restore@v4.1.2
+      uses: actions/cache/restore@v4.2.0
       with:
         path: |
           ~/.cargo/bin/