Skip Go linting for plugins with no schemas

For example, plugins like LogExplorer that only provide frontend
components (Explore views) don't have a `schemas/` directory and should
be skipped.

Signed-off-by: Jeremy Rickards <jeremy.rickards@sap.com>

Author: rickardsjp

scripts/golangci-lint/golangci-lint.go

@@ -25,6 +25,13 @@ func main() {
 	var isError bool
 
 	for _, workspace := range npm.MustGetWorkspaces(".") {
+		schemasPath := workspace + "/schemas"
+		if _, err := os.Stat(schemasPath); os.IsNotExist(err) {
+			// No schemas, skip go validation
+			logrus.Infof("skipping golangci-lint for %s (no schemas)", workspace)
+			continue
+		}
+
 		cmd := exec.Command("golangci-lint", "run")
 		cmd.Dir = workspace
 		cmd.Stdout = os.Stdout