[DOC] fix JSON typo in config in FAQ

[Remi-Gau]

Changes proposed in this pull request

minor fix to make the default config in the FAQ JSON valid for an easier copy-paste-adapt

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[codecov-commenter]

Codecov Report

Merging #2771 (7cd393d) into master (7f68f59) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master    #2771   +/-   ##
=======================================
  Coverage   46.08%   46.08%           
=======================================
  Files          44       44           
  Lines        3333     3333           
=======================================
  Hits         1536     1536           
  Misses       1797     1797           

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