Update on empty existing groupchoice options

[voegii]

When

• we have no groupchoice options (this can happen on a restore or an import),
• and we go to groupchoice settings
• and we add some groups
• and we want to save we receive this error message: "Could not update choicegroup".

[lucaboesch]

@ndunand A lecturer encountered this as well on our place, we do try the fix https://github.com/ndunand/moodle-mod_choicegroup/pull/190 and then we'll report back.

[ndunand]

Thanks @lucaboesch you input will be valued. We just don't want to induce any regressions but we'll take the time to review this in the near future.

[lucaboesch]

Dear @ndunand I can confirm the fix works. Of course, and I know that you are aware of this, I can not stress enough on how much Behat tests do help for regression prevention.

[NicoAlexH]

Fixed by merging https://github.com/ndunand/moodle-mod_choicegroup/pull/190