[QGIS-Developer] Relation reference widget: flaky test, final notice!

[Nyall Dawson]

Hi list,

I'm about to completely disable the relation reference widget test on
the CI -- it's been broken for about a week now, starting with flaky
failures and now completely crashing.

There's been a lot of different devs recently working on this widget,
and I suspect the current CI failures are a real issue caused as
fallout of this work.

If you've been working on this widget lately, please checkout the test
failures and see if your work caused it!

Nyall