Stop modifying behavior of yaml on load

[gluap]

Only modify a copy of SafeLoader to ensure that we don't change the behaviour of pyyaml for everyone.

Fixes #1825

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

❗ No coverage uploaded for pull request base (main@b4d6bf7). Click here to learn what that means.

Additional details and impacted files

@@           Coverage Diff           @@
##             main    #1826   +/-   ##
=======================================
  Coverage        ?   98.98%           
=======================================
  Files           ?       37           
  Lines           ?     4153           
  Branches        ?      967           
=======================================
  Hits            ?     4111           
  Misses          ?       26           
  Partials        ?       16           

Flag	Coverage Δ
unittests	98.67% <0.00%> (?)

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[codspeed-hq]

CodSpeed Performance Report

Merging #1826 will not alter performance

_{Comparing gluap:patch-1 (c85287b) with main (b4d6bf7)}

Summary

✅ 29 untouched benchmarks

[gluap]

Note that CodeQL is happy now - the failing tests seem to be down to problems with the upload of coverage because the github workflow is missing a token to upload to codecov.io - likely unrelated to the content of the PR, as nothing in that direction has changed.

[koxudaxi]

@gluap
Thank you for creating the PR.
you are right. we should copy it.

Note that CodeQL is happy now - the failing tests seem to be down to problems with the upload of coverage because the github workflow is missing a token to upload to codecov.io - likely unrelated to the content of the PR, as nothing in that direction has changed.

OK, I will fix it to merge the PR.