Make quad integration measures stateless

[mmahsereci]

In a Nutshell

This PR removes the default rng from the quad integration measures. Further, some long overdue shape tests for the sample method of the measures are added.

Detailed Description

na

Related Issues

Closes #...

[codecov]

Codecov Report

Merging #748 (75d4d48) into main (d94ff24) will increase coverage by 0.02%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##             main     #748      +/-   ##
==========================================
+ Coverage   90.69%   90.71%   +0.02%     
==========================================
  Files         206      206              
  Lines        7638     7638              
  Branches      982      982              
==========================================
+ Hits         6927     6929       +2     
+ Misses        479      478       -1     
+ Partials      232      231       -1     

Impacted Files	Coverage Δ
.../quad/integration_measures/_integration_measure.py	100.00% <ø> (ø)
...num/quad/integration_measures/_lebesgue_measure.py	100.00% <ø> (ø)
src/probnum/quad/_utils.py	100.00% <100.00%> (+6.45%)	⬆️

[tskarvone]

Looks good to me. As a user, I personally find it a bit annoying to have to provide an rng myself, but there is probably a good reason for this change.

[mmahsereci]

Looks good to me. As a user, I personally find it a bit annoying to have to provide an rng myself, but there is probably a good reason for this change.

It's mostly in preparation for #581 . See #744 (comment)

[mmahsereci]

The tox docs build seems to have failed when merging into main. I am not reverting though as the RTD build seems fine. Don't have time too look into it right away unfortunately. pinging @JonathanWenger for info.

[JonathanWenger]

@mmahsereci Should be fixed now in #754 .