Fix TypeSystem test that runs TypeSystem/Schema test with the current dir that it does not expect.

The `golden` contents for `TypeSystem/Schema` are symlinked to the current dir of the `TypeSystem` test run, to be found via a path relative to the current dir by the `TypeSystem/Schema` test that is called as a part of the `TypeSystem` test.

Author: sompylasar

TypeSystem/golden/smoke_test_struct.ts

@@ -0,0 +1 @@
+../Schema/golden/smoke_test_struct.ts