github: workflows: Add ccache for mac build

Signed-off-by: Patrick José Pereira <patrickelectric@gmail.com>

.github/workflows/buildQGCandDeploy.yml

@@ -29,6 +29,20 @@ jobs:
         with:
           submodules: recursive
 
+      - name: Cache
+        uses: actions/cache@v2
+        id: cache
+        with:
+          path: ~/.ccache
+          key: ${{ runner.os }}-mac-ccache-${{ github.sha }}
+          restore-keys: |
+            ${{ runner.os }}-mac-ccache-${{ github.sha }}
+            ${{ runner.os }}-mac-ccache-
+
+      - name: Install ccache
+        run: |
+          brew install ccache
+
       - name: install QT via action
         uses: jurplel/install-qt-action@v2
         with: 
@@ -51,8 +65,13 @@ jobs:
         working-directory: ${{ runner.temp }}/shadow_build_dir
         run:  |
               export JOBS=$((`sysctl -n hw.ncpu`+1))
-              qmake -r ${ACTIONS_BUILD_DIR}/qgroundcontrol.pro CONFIG+=${CONFIG}
+              export LIBRARY_PATH=/Library/Frameworks/GStreamer.framework/Versions/1.0/lib/
+              export CCACHE_DIR=~/.ccache
+              ccache -s
+              ccache -z
+              qmake -r ${ACTIONS_BUILD_DIR}/qgroundcontrol.pro CONFIG+=${CONFIG} CONFIG+=ccache
               make -j$JOBS
+              ccache -s
 
       - name: Upload build artifacts to release
         uses: svenstaro/upload-release-action@v2