chore(ci): upgrade to codecov v4

[thomasrockhu-codecov]

No description provided.

[codecov]

Codecov Report

Merging #27 (623f3ad) into main (9a3b0dd) will decrease coverage by 0.10%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main      #27      +/-   ##
==========================================
- Coverage   11.66%   11.57%   -0.10%     
==========================================
  Files           2        2              
  Lines         180      216      +36     
  Branches       27       34       +7     
==========================================
+ Hits           21       25       +4     
- Misses        135      167      +32     
  Partials       24       24              

Flag	Coverage Δ
unittests	11.57% <ø> (-0.10%)	⬇️

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

see 2 files with indirect coverage changes