[CI] cache west modules

.gitea/workflows/build.yml

@@ -18,6 +18,24 @@ jobs:
       - name: Checkout
         uses: actions/checkout@v3
 
+      - name: Cache west modules
+        uses: actions/cache@v3
+        env:
+          cache-name: cache-zephyr-modules
+        with:
+          path: |
+            modules/
+            tools/
+            zephyr/
+            bootloader/
+          key: ${{ runner.os }}-build-${{ env.cache-name }}-${{ hashFiles('app/west.yml') }}
+          restore-keys: |
+            ${{ runner.os }}-build-${{ env.cache-name }}-
+            ${{ runner.os }}-build-
+            ${{ runner.os }}-
+        timeout-minutes: 2
+        continue-on-error: true
+
       - name: West Init
         run: west init -l config