dispatch: set ui.insecureconnections when --insecure is used

mercurial/dispatch.py

@@ -829,6 +829,8 b' def _dispatch(req):'
 
     if cmdoptions.get('insecure', False):
         for ui_ in uis:
+            ui_.insecureconnections = True
+            # TODO remove once consumers are gone.
             ui_.setconfig('web', 'cacerts', '!', '--insecure')
 
     if options['version']: