fix: make //js/private:enable_runfiles explicitly have `//visibilit…

…y:public` (#301)

This is a direct dependency of all `js_binary()` targets and is currently `//visibility:public` by default, however this behavior is changing and can be opted in early via the [`--incompatible_config_setting_private_default_visibility`](https://bazel.build/reference/command-line-reference#flag--incompatible_config_setting_private_default_visibility) flag. Making this target explicitly public passes the build with that flag.

js/private/BUILD.bazel

@@ -12,6 +12,7 @@ exports_files(["js_binary.sh.tpl"])
 config_setting(
     name = "enable_runfiles",
     values = {"enable_runfiles": "true"},
+    visibility = ["//visibility:public"],
 )
 
 bzl_library(