switch p4est_destroy and p4est_connectivity_destroy in docs

[ranocha]

Based on the suggestion of @lcw, I changed the order of p4est_destroy and p4est_connectivity_destroy in the docs. This should fix #119.

We should get a new release (at least of the stable docs) after merging this.

[JoshuaLampert]

Did you perform some tests that after this there is no segfault anymore?

[JoshuaLampert]

Ok, I just did some tests. After several tries with the new order, there was no single segfault. Before it was something like roughly every second or third time. So this looks promising. Thanks again @lcw for the pointer and thanks @ranocha for fixing this!

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 17.80%. Comparing base (af7b234) to head (64413c1).

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #120   +/-   ##
=======================================
  Coverage   17.80%   17.80%           
=======================================
  Files           3        3           
  Lines        1427     1427           
=======================================
  Hits          254      254           
  Misses       1173     1173           

Flag	Coverage Δ
unittests	17.80% <ø> (ø)

Flags with carried forward coverage won't be shown. Click here to find out more.

☔ View full report in Codecov by Sentry.
📢 Have feedback on the report? Share it here.