Improve instructions for setting up the development environment

[jhp0tter]

This is another attempt at #1024, because I think there is still some room for improvement after @trwnh's edits.

Changes:

• Fix commands and clarify instructions.
• Add some tips for operating system-specific quirks.
• Remove typographic quotes.
• Add a trailing newline.

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[github-actions[bot]]

This pull request has merge conflicts that must be resolved before it can be merged.

[vmstan]

@jhp0tter can you please rebase?

[jhp0tter]

@vmstan Does this work?

[github-actions[bot]]

This pull request has resolved merge conflicts and is ready for review.