[DS-1300] Add a fix for the auto-submit auth form functionality of the openy_gc_auth_example module

[aleevas]

Related Issue/Ticket: DS-1300

Steps to test:

• [ ] go to /virtual-y-login page
• [ ] Open the DevTools
• [ ] verify that you don't see the any error messages in the console
• [ ] log in as admin
• [ ] go to /admin/openy/virtual-ymca/gc-auth-settings/provider/dummy
• [ ] Turn on the Autosubmit flag and save the form
• [ ] go to /virtual-y-login page as anonym
• [ ] verify that you automatically logged in to Virtual Y account

Quality checks:

Please check these boxes to confirm this PR covers the following cases:

• Maintaining our upgrade path is essential. Check one or the other:
  • [ ] This PR provides updates via hook_update_N or other means.
  • [ ] No updates are necessary for this change.
• Front end fixes should be tested against all of the Open Y Themes.
  • [ ] Tested against Carnation
  • [ ] Tested against Lily
  • [ ] Tested against Rose
  • [ ] This change does not contain front-end fixes.
• [ ] I have flagged this PR "Needs Review" or pinged the VY devs/QA team in Slack