CI: address actions/cache warning and always upload cache.

.github/workflows/sub_buildUbuntu.yml

@@ -107,9 +107,10 @@ jobs:
           compiler: ${{ env.CXX }}
           qt_major_version: 5
       - name: Restore Compiler Cache
-        uses: actions/cache@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        id: cache-restore
+        if: always()
+        uses: actions/cache/restore@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
         with:
-          save-always: true
           path: ${{ env.CCACHE_DIR }}
           key: FC-${{ steps.genCacheKey.outputs.cacheKey }}-${{ github.ref }}-${{ github.run_id }}
           restore-keys: |
@@ -190,6 +191,15 @@ jobs:
           testCommand: xvfb-run FreeCAD -t 0
           logFile: ${{ env.logdir }}TestGUIInstall.log
           reportFile: ${{env.reportdir}}${{ env.reportfilename }}
+
+      - name: Save Compiler Cache
+        id: cache-save
+        if: always()
+        uses: actions/cache/save@5a3ec84eff668545956fd18022155c47e93e2684 # v4.2.3
+        with:
+          path: ${{ env.CCACHE_DIR }}
+          key: FC-${{ env.cacheKey }}-${{ github.ref }}-${{ github.run_id }}
+
       - name: Upload logs
         if: always()
         uses: actions/upload-artifact@ea165f8d65b6e75b540449e92b4886f43607fa02 # v4.6.2