Fix version checker

[haakonvt]

After version 5.3.1, a hyphen in the package name became an underscore, and thus the regex stopped working.

This PR fixes the regex and removes all code related to manually parsing versions.

[codecov]

Codecov Report

Attention: Patch coverage is 8.69565% with 21 lines in your changes missing coverage. Please review.

Project coverage is 90.61%. Comparing base (49c87bd) to head (30eff37).
Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
cognite/client/utils/_version_checker.py	0.00%	19 Missing ⚠️
cognite/client/config.py	33.33%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #2080      +/-   ##
==========================================
+ Coverage   90.49%   90.61%   +0.12%     
==========================================
  Files         141      141              
  Lines       22566    22516      -50     
==========================================
- Hits        20421    20403      -18     
+ Misses       2145     2113      -32     

Files with missing lines	Coverage Δ
cognite/client/_version.py	100.00% <100.00%> (ø)
cognite/client/utils/_auxiliary.py	96.64% <ø> (+3.56%)	⬆️
cognite/client/config.py	93.93% <33.33%> (+0.87%)	⬆️
cognite/client/utils/_version_checker.py	0.00% <0.00%> (-22.23%)	⬇️

... and 2 files with indirect coverage changes