add some links

Author: zloirock

packages/core-js/modules/es.map.group-by.js

@@ -14,6 +14,7 @@ var get = MapHelpers.get;
 var set = MapHelpers.set;
 var push = uncurryThis([].push);
 
+// https://bugs.webkit.org/show_bug.cgi?id=271524
 var DOES_NOT_WORK_WITH_PRIMITIVES = IS_PURE || fails(function () {
   return Map.groupBy('ab', function (it) {
     return it;

packages/core-js/modules/es.object.group-by.js

@@ -13,6 +13,7 @@ var nativeGroupBy = Object.groupBy;
 var create = getBuiltIn('Object', 'create');
 var push = uncurryThis([].push);
 
+// https://bugs.webkit.org/show_bug.cgi?id=271524
 var DOES_NOT_WORK_WITH_PRIMITIVES = !nativeGroupBy || fails(function () {
   return nativeGroupBy('ab', function (it) {
     return it;