Add --skip-sign flat to goreleaser ran in tests

We only want to sign artifacts and containers when releasing, not
necessarily when testing PRs.

Signed-off-by: Juan Antonio Osorio <juan.osoriorobles@eu.equinix.com>

.github/workflows/test.yaml

@@ -113,7 +113,7 @@ jobs:
       uses: goreleaser/goreleaser-action@v3
       with:
         version: v1.4.1
-        args: release --snapshot --rm-dist --skip-publish --timeout 90m
+        args: release --skip-sign --snapshot --rm-dist --skip-publish --timeout 90m
 
   build-documents:
     name: Documentation Test