Add tests for `recursive_unicode` function #3043

Job	Run time
gatekeeper	4s
env	1s
changes	2s
documentation	0s
application_tester	0s
guitest	0s
mac	0s
pytest	0s
ubuntu	0s
windows	0s
application_tester_draft / run (ubuntu-latest)	4m 1s
guitest_draft / run (windows-latest)	3m 34s
coverage_draft / generate and upload	4m 4s
scripttest_draft / run	1m 55s
	13m 41s

Provide feedback