Use the tmpdir fixture for tests that create files

[olliesilvester]

Fixes #994

To test:

1. Run tests
2. Check if change is useful/makes sense

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Comparison is base (372887a) 93.67% compared to head (5e2067a) 93.49%.
Report is 1 commits behind head on main.

❗ Current head 5e2067a differs from pull request most recent head c201b10. Consider uploading reports for the commit c201b10 to get more accurate results

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #995      +/-   ##
==========================================
- Coverage   93.67%   93.49%   -0.19%     
==========================================
  Files          56       56              
  Lines        2704     2704              
==========================================
- Hits         2533     2528       -5     
- Misses        171      176       +5     

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[d-perl]

I didn't know about this fixture, this does seem nice!

It doesn't seem like your temp_directory fixture is doing anything different to the builtin tmpdir? so I think we can just use that. Also in that case you can delete the .../test_data/scratch directory and .gitignore entries

[olliesilvester]

thanks, didnt see it was in the gitignore

[d-perl]

Looks good, thanks!

[DominicOram]

Nit: Can you tidy up the PR name to make more sense to a user please?