Fix typo in README.md

[jonathanBieler]

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[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 97.78%. Comparing base (ca4ec9c) to head (7f14b49).

Additional details and impacted files

@@           Coverage Diff           @@
##           master      #41   +/-   ##
=======================================
  Coverage   97.78%   97.78%           
=======================================
  Files          14       14           
  Lines         766      766           
=======================================
  Hits          749      749           
  Misses         17       17           

Flag	Coverage Δ
unittests	97.78% <ø> (ø)

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