Revert "fix(router): update symbols (angular#60233)"

This reverts commit 7bcdf7c.
The original change causing CI failures was affecting the main branch only, reverting from the patch branch (since it causes CI failures).

Author: AndrewKushnir

packages/core/test/bundling/router/bundle.golden_symbols.json

@@ -694,7 +694,7 @@
   "standardizeConfig",
   "storeLViewOnDestroy",
   "stringify",
-  "stringify13",
+  "stringify12",
   "stringifyCSSSelector",
   "stripTrailingSlash",
   "subscribeOn",