4311 - Missing display name fix

[WillNigel23]

The fix works in 2 parts:

We update the callback update_display_name to set real_name and display_name to nil in case the string value is blank. This will prevent new records with ' ' display_name values from being created.

Second is we update the display_name override to detect [:display_name] presence, otherwise use login. This will help us so that we don't need to do a migration to fix bad data

[saracarl]

This is fine, but it doesn't address what I suspect is the real cause of owner names being blank, which is the redirect to a different view when you encounter an error creating your trial account.

If you get errors sign up here (users/new_trial):

You get redirected to here (users):

[WillNigel23]

Owner names being saved in db as blank does not have much impact.

As long as real_name is set to something blank (i.e: nil, " " empty string, etc), we will be using 'self[:login]' which is always true.

At the end of the day, we save as nil if it is blank (which is the callback fix here).

[WillNigel23]

On the redirect part, this seems like a separate bug if there are sign up errors in new_trial that redirects to a different sign up form route.

[WillNigel23]

If in case we add more registration_type, we can easily add it here