fix(zone.js): restore definition of global (#31453)

This partially reverts some changes from 71b9371180 (diff-dd469785fca8680a5b33b1e81c5cfd91R1420)
These broke the g3sync of zone.js because we use the output of the TypeScript compiler directly, rather than rely on the rollup commonjs plugin to define the global symbol

PR Close #31453

packages/zone.js/lib/zone-spec/fake-async-test.ts

@@ -557,4 +557,4 @@
   // Export the class so that new instances can be created with proper
   // constructor params.
   (Zone as any)['FakeAsyncTestZoneSpec'] = FakeAsyncTestZoneSpec;
-})(global);
+})(typeof window === 'object' && window || typeof self === 'object' && self || global);