[ghactions] Cache Qt dependencies for building Windows Companion (#1431)

* [action] Cache QT install files
* Take into account two windows builds

Note: If for any reason the cache is corrupted, the cache key will need to be updated to make it re-build.

.github/workflows/win-cpn-32.yml

@@ -65,10 +65,18 @@ jobs:
                                 mingw-w64-i686-clang \
                                 mingw-w64-i686-nsis
           pip install Pillow clang
-          
+
+      - name: Cache Qt
+        id: cache-qt
+        uses: actions/cache@v1  # not v2!
+        with:
+          path: ../Qt
+          key: win32-QtCache
+
       - name: Install Qt
         uses: jurplel/install-qt-action@v2
         with:
+          cached: ${{ steps.cache-qt.outputs.cache-hit }}
           version: ${{ env.QT_VERSION }}
           arch: ${{ env.MINGW_VERSION }}
 

.github/workflows/win_cpn.yml

@@ -68,10 +68,18 @@ jobs:
                                 mingw-w64-x86_64-clang \
                                 mingw-w64-x86_64-nsis
           pip install Pillow clang
-          
+
+      - name: Cache Qt
+        id: cache-qt
+        uses: actions/cache@v1  # not v2!
+        with:
+          path: ../Qt
+          key: win64-QtCache
+
       - name: Install Qt
         uses: jurplel/install-qt-action@v2
         with:
+          cached: ${{ steps.cache-qt.outputs.cache-hit }}
           version: ${{ env.QT_VERSION }}
           arch: ${{ env.MINGW_VERSION }}