Cache in master branch

.github/workflows/cache.yml

@@ -0,0 +1,46 @@
+# Commented while we wait for the new Electron versions to ship
+
+name: Cache
+
+on:
+  push:
+    branches:
+      - "master"
+
+jobs:
+  release:
+    runs-on: ${{ matrix.os }}
+    timeout-minutes: 30
+    env:
+      ACTIONS_ALLOW_UNSECURE_COMMANDS: true
+
+    strategy:
+      matrix:
+        os: [macos-10.15, windows-latest]
+
+      - name: Check out Git repository
+        uses: actions/checkout@v2
+
+      - name: Install Node.js, NPM and Yarn for Mac
+        if: startsWith(matrix.os, 'macos')
+        uses: actions/setup-node@v1
+        with:
+          node-version: 15
+
+      - name: Install Node.js, NPM and Yarn for Windows
+        if: startsWith(matrix.os, 'windows')
+        uses: actions/setup-node@v1
+        with:
+          node-version: 12
+
+      - uses: actions/[email protected]
+        with:
+          path: "**/node_modules"
+          key: ${{ runner.os }}-modules-${{ hashFiles('**/yarn.lock') }}
+
+      - name: Yarn
+        run: |
+          yarn install
+          yarn clean
+          yarn node-gyp clean
+