BUILD: fix gazelle repo file marker

Change-Id: I2ba10be7f4af784782d684b662529f926c348232
diff --git a/WORKSPACE b/WORKSPACE
index 9474e10..031d55a 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -82,6 +82,7 @@
 go_rules_dependencies()
 go_register_toolchains()
 
+# gazelle:repository_macro third_party/go/repositories.bzl%go_repositories
 load("@bazel_gazelle//:deps.bzl", "gazelle_dependencies")
 gazelle_dependencies()