docs: correctly format code block

[alexframe]

Pull Request check-list

Please make sure to review and check all of these items:

• Does npm run test or npm run test-DIALECT pass with this change (including linting)?
• Does the description below contain a link to an existing issue (Closes #[issue]) or a description of the issue you are solving?
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Description of change

Resolves #10744 by changing incorrectly formatted code block from json to javascript.

[codecov]

Codecov Report

Merging #10745 into master will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##           master   #10745   +/-   ##
=======================================
  Coverage   96.31%   96.31%           
=======================================
  Files          93       93           
  Lines        8980     8980           
=======================================
  Hits         8649     8649           
  Misses        331      331

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[sushantdhiman]

🎉 This PR is included in version 5.3.0 🎉

The release is available on:

• npm package (@latest dist-tag)
• GitHub release

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