pre-commit: pyupgrade

[Borda]

What does this PR do?

Fixes # (issue)

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• Did you write any new necessary tests? [not needed for typos/docs]
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[codecov]

Codecov Report

Merging #658 (5e07281) into master (5f11ebc) will decrease coverage by 0.00%.
The diff coverage is 88.46%.

@@            Coverage Diff             @@
##           master     #658      +/-   ##
==========================================
- Coverage   90.59%   90.58%   -0.01%     
==========================================
  Files         173      173              
  Lines        9235     9232       -3     
==========================================
- Hits         8366     8363       -3     
  Misses        869      869              

Flag	Coverage Δ
unittests	90.58% <88.46%> (-0.01%)	⬇️

Flags with carried forward coverage won't be shown. Click here to find out more.

Impacted Files	Coverage Δ
flash/core/data/data_source.py	94.61% <0.00%> (ø)
flash/core/serve/dag/rewrite.py	94.96% <0.00%> (ø)
flash/setup_tools.py	61.29% <0.00%> (ø)
flash/core/data/transforms.py	100.00% <100.00%> (ø)
flash/core/serve/component.py	94.33% <100.00%> (ø)
flash/core/serve/dag/task.py	97.84% <100.00%> (-0.04%)	⬇️
flash/core/serve/types/label.py	100.00% <100.00%> (ø)
flash/core/serve/types/repeated.py	97.14% <100.00%> (ø)
flash/image/classification/backbones/resnet.py	90.85% <100.00%> (ø)
flash/image/detection/serialization.py	94.23% <100.00%> (ø)
... and 5 more

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