doc: formatted example clone repo command as codeblock

[travisamartin]

Proposed changes

This PR makes the following documentation change:

• Formats the example command for cloning the repo as a codeblock vs in-line code. The in-line format wraps and a user commented on the ending period as an issue (when copying).

The codeblock resolved the wrapping issue and removes the terminating period. Plus, it adds the Copy button.

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Checklist

Before creating a PR, run through this checklist and mark each as complete.

• I have read the CONTRIBUTING doc
• I have added tests that prove my fix is effective or that my feature works
• I have checked that all unit tests pass after adding my changes
• I have updated necessary documentation
• I have rebased my branch onto main
• I will ensure my PR is targeting the main branch and pulling from my branch from my own fork

[github-actions]

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