go.mod: update modules

.github/workflows/ci-cd.yml

@@ -17,7 +17,7 @@ jobs:
       - name: Install go
         uses: actions/setup-go@v2
         with:
-          go-version: 1.15.x
+          go-version: 1.16.x
 
       - name: Check out source code
         uses: actions/checkout@v1
@@ -33,6 +33,7 @@ jobs:
           sudo snap install skopeo --edge --devmode
 
       - name: Run build and test
+        timeout-minutes: 30
         run: |
           cd $GITHUB_WORKSPACE && make