Prefer native buildifier suppressions over @lint-ignore BUILDIFIERLINT

Summary:
Buildifier has its own native syntax for this. Avoid mixing suppression
syntaxes by disallowing using Linttool's syntax (i.e. `lint-ignore`).

Reviewed By: dtolnay

Differential Revision: D55879633

fbshipit-source-id: 65d50db41e57f5d87008d8a58c63a2f08d1be49d

Author: zertosh

shim/target_determinator/macros/ci.bzl

@@ -8,9 +8,11 @@
 def _lbl(*_args):
     return ""
 
-def _package(_values, overwrite = False):
-    # @lint-ignore BUILDIFIERLINT
-    _ = overwrite
+def _package(
+        _values,
+        # starlark-lint-disable unused-argument
+        overwrite = False):  # @unused
+    pass
 
 ci = struct(
     package = _package,