Check URL on Create OpenID Connect provider

[6543]

source: #9833 (comment)

"...some feedback on whether the URL is correct (like checking the response of the URL to see that it does return something that looks like a .well-known/openid-configuration) rather than blindly accepting the URL would be a big improvement in user experience."

[siddhant94]

Hey @techknowlogick @zeripath , auto-discover-url is being used in runAddOauth() & runUpdateOauth() . I was thinking of adding check for valid URL in parseOAuth2Config() so that it could be in a single place for everybody to use, but only runAddOauth() uses this parse method. So any suggestions regarding where the check could be placed?