(core) Simplify InitNewDoc since the timezone and locale is never actually used

Summary: InitNewDoc is essentially only used to generate initialDocSql, so it doesn't make sense to set the timezone and locale. They are always set when actually creating a new doc anyway. Discussed in https://grist.slack.com/archives/C0234CPPXPA/p1650312714217089.

Test Plan: this

Reviewers: paulfitz

Reviewed By: paulfitz

Differential Revision: https://phab.getgrist.com/D3394

sandbox/grist/useractions.py

@@ -275,14 +275,12 @@ class UserActions(object):
   #----------------------------------------
 
   @useraction
-  def InitNewDoc(self, timezone, locale):
+  def InitNewDoc(self):
     creation_actions = schema.schema_create_actions()
     self._engine.out_actions.stored.extend(creation_actions)
     self._engine.out_actions.direct += [True] * len(creation_actions)
     self._do_doc_action(actions.AddRecord("_grist_DocInfo", 1,
-                                          {'schemaVersion': schema.SCHEMA_VERSION,
-                                           'timezone': timezone,
-                                           'documentSettings': json.dumps({'locale': locale})}))
+                                          {'schemaVersion': schema.SCHEMA_VERSION}))
 
     # Set up initial ACL data.
     # NOTE The special records below are not actually used. They were intended for obsolete ACL