fix(ci): export GOPROXY as direct

Author: mselim00

.github/actions/ci/kubetest2/action.yaml

@@ -29,7 +29,7 @@ runs:
       run: |
         export PATH=${PATH}:$(go env GOPATH)/bin
         # old versions of packages are sometimes cached by the proxy, just disable it
-        GOPROXY=direct
+        export GOPROXY=direct
         go install sigs.k8s.io/kubetest2/...@latest
         go install github.com/aws/aws-k8s-tester/...@HEAD