Fix mypy in utilities.distributed

[stancld]

What does this PR do?

Part of #7037. This PR disentangles large #7218. It fixes mypy typing in utilities.device_parser.py.

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[codecov]

Codecov Report

Merging #8201 (876703a) into master (963c267) will decrease coverage by 4%.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #8201    +/-   ##
=======================================
- Coverage      93%     89%    -4%     
=======================================
  Files         169     169            
  Lines       14072   14071     -1     
=======================================
- Hits        13043   12464   -579     
- Misses       1029    1607   +578     

[stale]

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