Return an error if repo/ref not detected (#382)

* return an error if repo/ref not detected

* Test detect-env

* remove debugging

Co-authored-by: laurentsimon <64505099+laurentsimon@users.noreply.github.com>

.github/actions/detect-workflow/main.go

@@ -125,6 +125,13 @@ func (a *action) getRepoRef(ctx context.Context) (string, string, error) {
 		ref = refParts[1]
 	}
 
+	if repository == "" {
+		return "", "", errors.New("no repository detected")
+	}
+	if ref == "" {
+		return "", "", errors.New("no ref detected")
+	}
+
 	return repository, ref, nil
 }