[#3725] Add invalid forms (configuration and logic rules) to the email digest

[vaszig]

Fixes #3725 partially

[vaszig]

This should wait for #4163 to be approved because it also touches some files from there.
This was merged.

[codecov]

Codecov Report

Attention: Patch coverage is 98.97959% with 1 line in your changes missing coverage. Please review.

Project coverage is 96.24%. Comparing base (4734c03) to head (8ef40fb).
Report is 741 commits behind head on master.

Files	Patch %	Lines
src/openforms/emails/digest.py	98.88%	0 Missing and 1 partial ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4198      +/-   ##
==========================================
+ Coverage   96.14%   96.24%   +0.09%     
==========================================
  Files         731      731              
  Lines       23604    23683      +79     
  Branches     2773     2790      +17     
==========================================
+ Hits        22695    22793      +98     
+ Misses        643      622      -21     
- Partials      266      268       +2     

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[sergei-maertens]

I think this raises some questions too:

• Should we block JSON logic like {"var": {"var": "a"}}? This seems awfully complex for the sort of things we'd like to support. Blocking it allows us to build a logic evaluation dependency tree.

[sergei-maertens]

Almost there!

[sergei-maertens]

(no need to fix this, just for the future)

the list comprehension isn't necessary, get_inputs_keys() already returns a list of input vars:

Suggested change

	form_logics_vars += [
	var
	for var in introspect_json_logic(expression).get_input_keys()
	]
	form_logics_vars += introspect_json_logic(expression).get_input_keys()