Update actions/setup-python action to v4

[renovate]

This PR contains the following updates:

Package	Type	Update	Change
actions/setup-python	action	major	v2 -> v4

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Release Notes

actions/setup-python (actions/setup-python)

v4

Compare Source

v3

Compare Source

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Configuration

📅 Schedule: Branch creation - At any time (no schedule defined), Automerge - At any time (no schedule defined).

🚦 Automerge: Disabled by config. Please merge this manually once you are satisfied.

♻ Rebasing: Whenever PR becomes conflicted, or you tick the rebase/retry checkbox.

🔕 Ignore: Close this PR and you won't be reminded about this update again.

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• If you want to rebase/retry this PR, check this box

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[codecov]

Codecov Report

Merging #9 (3bf77ed) into main (e5f68c3) will not change coverage.
Report is 1 commits behind head on main.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main       #9   +/-   ##
=======================================
  Coverage   78.40%   78.40%           
=======================================
  Files           7        7           
  Lines          88       88           
  Branches       24       24           
=======================================
  Hits           69       69           
  Misses          3        3           
  Partials       16       16           

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