fix readme rendering

[jesterhazy]

Description of changes:

fix readme rendering

Merge Checklist

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• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works (if appropriate)
• I have updated the changelog with a description of my changes (if appropriate)
• I have updated any necessary documentation (if appropriate)

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[nadiaya]

wow

[codecov-io]

Codecov Report

Merging #464 into master will not change coverage.
The diff coverage is n/a.

@@          Coverage Diff          @@
##           master   #464   +/-   ##
=====================================
  Coverage      94%    94%           
=====================================
  Files          57     57           
  Lines        4284   4284           
=====================================
  Hits         4027   4027           
  Misses        257    257

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