Bugfix fetchart

[MatMacinf]

Description

Situation mentioned bu user in the issue was very hard to copy and to understand, the issue was not in fetchers plugin but in
util.move() function and its fallback
First tries to copy file (cannot between disk (E: -> C: in user situation)
Then creating a copy tmp file and tries to move, I this moment between creating tmp file and moving it Foobar2000 wins race and block file. Move() tries to copy but can't now in section finally it tires to delete tmp file, which is blocked so cannot be deleted. My fix was to add try, except clause to catch error in finally section and raise FileSystemError with information that tmp file was not deleted.

Added test and also reproducing this situation locally on windows machine, added changeling entry, no documentation provided - It's small bug fix with classic try except clause
Fixes #6193 .

(...)

To Do

• [x ]~ Documentation. ~(If you've added a new command-line flag, for example, find the appropriate page under docs/ to describe it.)
• [x ] Changelog. (Add an entry to docs/changelog.rst to the bottom of one of the lists near the top of the document.)
• [x ] Tests. (Very much encouraged but not strictly required.)

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 68.91%. Comparing base (4882b6b) to head (73bd048).
⚠️ Report is 3 commits behind head on master.
✅ All tests successful. No failed tests found.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #6319      +/-   ##
==========================================
+ Coverage   68.77%   68.91%   +0.13%     
==========================================
  Files         140      140              
  Lines       18619    18622       +3     
  Branches     3054     3054              
==========================================
+ Hits        12806    12833      +27     
+ Misses       5165     5140      -25     
- Partials      648      649       +1     

Files with missing lines	Coverage Δ
beets/util/__init__.py	83.80% <100.00%> (+4.78%)	⬆️

... and 1 file with indirect coverage changes

🚀 New features to boost your workflow:

• 📦 JS Bundle Analysis: Save yourself from yourself by tracking and limiting bundle sizes in JS merges.