implement go packages cache

Author: teddy931130

.github/workflows/build.yml

@@ -38,11 +38,12 @@ jobs:
           fetch-depth: 0
           ref: ${{ github.ref_name }}
 
-      ### NOT using dependency caches, since using GitHub-hosted runners. More info at the URL below:
+      ### Need to be careful with dependency caches, since using GitHub-hosted runners. More info at the URL below:
       ### https://docs.github.com/en/actions/writing-workflows/choosing-what-your-workflow-does/caching-dependencies-to-speed-up-workflows#about-caching-workflow-dependencies
-      # - uses: actions/setup-go@v5
-      #   with:
-      #     go-version-file: "go.mod"
+      - name: Cache go.mod packages
+        uses: actions/setup-go@v5
+        with:
+          go-version-file: "go.mod"
 
       - name: Configure AWS Credentials
         uses: aws-actions/configure-aws-credentials@v4