feat: add submodule cache to build.yaml

Author: jsjoeio

.github/workflows/build.yaml

@@ -31,7 +31,6 @@ jobs:
         uses: actions/checkout@v3
         with:
           fetch-depth: 0
-          submodules: true
 
       - name: Install Node.js v16
         uses: actions/setup-node@v3
@@ -52,7 +51,7 @@ jobs:
 
       - name: Install dependencies
         if: steps.cache-root-node-mods.outputs.cache-hit != 'true'
-        run: yarn --frozen-lockfile
+        run: SKIP_SUBMODULE_DEPS=1 yarn --frozen-lockfile
 
       - name: Run yarn fmt
         run: yarn fmt
@@ -74,7 +73,24 @@ jobs:
         uses: actions/checkout@v3
         with:
           fetch-depth: 0
-          submodules: true
+
+      - name: Get submodule hash
+        id: submodule-hash
+        run: |
+          echo "::set-output name=key::$(git ls-tree HEAD lib/vscode)"
+
+      - name: Fetch submodule from cache
+        id: cache-submodule
+        uses: actions/cache@v3
+        with:
+          path: "lib/vscode/**"
+          key: submodule-hash-${{ steps.submodule-hash.outputs.key }}
+          restore-keys: |
+            submodule-hash-
+
+      - name: Checkout submodule
+        if: steps.cache-submodule.outputs.cache-hit != 'true'
+        run: git submodule update --init
 
       - name: Install quilt
         run: sudo apt update && sudo apt install quilt