Chore: add cache for github actions

.github/workflows/go.yml

@@ -13,8 +13,16 @@ jobs:
 
       - name: Check out code into the Go module directory
         uses: actions/checkout@v1
+      
+      - name: Cache go module
+        uses: actions/cache@v1
+        with:
+          path: ~/go/pkg/mod
+          key: ${{ runner.os }}-go-${{ hashFiles('**/go.sum') }}
+          restore-keys: |
+            ${{ runner.os }}-go-
 
-      - name: Get dependencies
+      - name: Get dependencies and run test
         run: |
           go test ./...