ci: use go.mod to get go version

Author: fabiomatavelli

.github/workflows/build.yml

@@ -33,7 +33,7 @@ jobs:
       - name: Set up Go
         uses: actions/setup-go@v3
         with:
-          go-version: 1.21.x
+          go-version-file: 'go.mod'
 
       - name: Build
         run: |

.github/workflows/testacc.yml

@@ -34,7 +34,7 @@ jobs:
       - name: Set up Go
         uses: actions/setup-go@v3
         with:
-          go-version: 1.21.x
+          go-version-file: 'go.mod'
       - name: Wait Cloudstack to be ready
         run: |
           echo "Starting Cloudstack health check"