Remove extra backtick

[mauricesvp]

PR Prelude

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Why this change is necessary and useful

Fixes extra backtick in README.

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This change is 

[codecov]

Codecov Report

Merging #4225 (3b607df) into master (c3c0332) will decrease coverage by 0.09%.
The diff coverage is n/a.

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #4225      +/-   ##
==========================================
- Coverage   89.67%   89.58%   -0.09%     
==========================================
  Files          34       34              
  Lines        4445     4445              
==========================================
- Hits         3986     3982       -4     
- Misses        459      463       +4     

[bstaletic]

Thanks!

Reviewed 1 of 1 files at r1, all commit messages.
Reviewable status: 0 of 2 LGTMs obtained (waiting on @mauricesvp)

[mergify]

Thanks for sending a PR!