Fix OSError: [Errno 9] Bad file descriptor

[iglooom]

The with statement closes fd on exit, and fchown takes a bad descriptor.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 85.19%. Comparing base (eb5705c) to head (f1aed63).
✅ All tests successful. No failed tests found.

Files with missing lines	Patch %	Lines
src/amd_debug/sleep_report.py	0.00%	2 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##           master      #42   +/-   ##
=======================================
  Coverage   85.19%   85.19%           
=======================================
  Files          36       36           
  Lines        8119     8119           
  Branches      766      766           
=======================================
  Hits         6917     6917           
  Misses        980      980           
  Partials      222      222           

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