[ci] Upgrade actions/cache to v3 (#294)

Author: WonyoungChoi

.github/workflows/build.yml

@@ -41,6 +41,13 @@ jobs:
           path: src/flutter
           fetch-depth: 0
 
+      - uses: actions/cache@v3
+        with:
+          path: src/out/${{ env.OUTPUT_NAME }}
+          key: out-build-${{ env.OUTPUT_NAME }}-${{ github.sha }}
+          restore-keys: |
+            out-build-${{ env.OUTPUT_NAME }}-
+
       - name: gclient sync
         run: |
           src/flutter/ci/tizen/gclient-prepare-sync.sh --reduce-deps --shallow-sync
@@ -195,6 +202,13 @@ jobs:
         with:
           path: src/flutter
 
+      - uses: actions/cache@v3
+        with:
+          path: src/out/${{ env.OUTPUT_NAME }}
+          key: out-macos-build-${{ env.OUTPUT_NAME }}-${{ github.sha }}
+          restore-keys: |
+            out-macos-build-${{ env.OUTPUT_NAME }}-
+
       - name: install depot_tools
         run: |
           git clone https://chromium.googlesource.com/chromium/tools/depot_tools.git