Back out "Oncall for BUCK project xplat/js/react-native-github/BUCK"

Summary:
Original commit changeset: 8f3e37917646

Original Phabricator Diff: D40460041 (dac6806559)

Reviewed By: GijsWeterings, arushikesarwani94

Differential Revision: D41119700

fbshipit-source-id: 5de6808a721efd0b9b765e52586155dd375c0fee

BUCK

@@ -29,8 +29,6 @@ load(
 )
 load("//tools/build_defs/third_party:yarn_defs.bzl", "yarn_workspace")
 
-oncall("react_native")
-
 RCTCXXBRIDGE_PUBLIC_HEADERS = {
     "React/" + x: "React/CxxBridge/" + x
     for x in [