Update readme with trivial change

[tomhamiltonstubber]

No description provided.

[codecov]

Codecov Report

Merging #26 (46f7176) into master (4ae59f2) will decrease coverage by 0.77%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master      #26      +/-   ##
==========================================
- Coverage   97.31%   96.54%   -0.78%     
==========================================
  Files           9        9              
  Lines         522      521       -1     
  Branches       95       94       -1     
==========================================
- Hits          508      503       -5     
- Misses          9       11       +2     
- Partials        5        7       +2     

Impacted Files	Coverage Δ
aioaws/core.py	97.95% <0.00%> (-2.05%)	⬇️
aioaws/s3.py	97.36% <0.00%> (-1.77%)	⬇️

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