typos in _koopman.py

[KirillShmilovich]

some typos fixed

[codecov]

Codecov Report

Merging #221 (9da2917) into main (38b0158) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main     #221   +/-   ##
=======================================
  Coverage   93.74%   93.74%           
=======================================
  Files         136      136           
  Lines       10807    10807           
=======================================
  Hits        10131    10131           
  Misses        676      676           

Impacted Files	Coverage Δ
deeptime/decomposition/_koopman.py	90.07% <ø> (ø)

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[clonker]

Thanks Kirill!