Fix multiple checkbox from relation ship custom field not loading

[peetCreative]

For detailed information please read:
https://www.drupal.org/project/webform_civicrm/issues/3494307

@KarinG proposed to open this PR.

Open TODO: Write tests.

[peetCreative]

@KarinG I implemented test, which passed partially.
For the first two, I have the impression, that it's not failing because of my new tests or code, what do you think?

[KarinG]

Well done - thank you for persevering. I will add this to my list to review.

[KarinG]

Hey Peter - looking at this now. Awesome that you got the test in!

My notes ->

1. Reproduced:
Checkboxes on Contact entity fields retrieve the correct values from the database -> Favourite Colours: red and white.
Checkboxes on Relationship entity fields are not retrieved -> Deutschland, Canada

Note: Partner 1 : Existing Contact -> Current User and Partner 2: Existing Contact -> Default value -> Relationship to: Partner 1 -> Specify Relationship

2. Reproduce in a test.
Making some small edits to your test - will push them to your branch.

[KarinG]

Ok waiting for these tests to fail. Back in a bit.

[KarinG]

civicrm extention dir is down -> "error_message": "It is not possible to contact the CiviCRM extensions directory. You may be missing out on the latest updates to extensions. Check that you can view the <a href="https://civicrm.org/extdir/ver=5.82.beta1|cms=Drupal8|ready=\">extension feed. If that works check that your webserver can make external HTTP requests."

[KarinG]

[KarinG]

Ok test now fails exactly where we need it to fail ->

Now adding your code fix back in:

[KarinG]

All tests are passing 🥳

And this is the test browser output ->
/screenshots.10.3._5.81._8.2%20(1)/Drupal_Tests_webform_civicrm_FunctionalJavascript_ContactRelationshipTest-8-87009787.html

I will pull this into webform-civicrm.io this week to run some final live checks and then we can merge it.

[peetCreative]

Is there some progress?

[KarinG]

I've not had a chance to live test/QA yet. I will get back to it (as I already spent time on this PR/editing your branch), but If you want to fast track this and if you're able to sponsor 1-2h of time then I can ask one of my team to help QA/review it and then I can release a new 6.x version.

[peetCreative]

Thanks for the notice. I fear as I'm employed myself for this project I cannot. :|
However it is not urgend by now.