[improve][doc] getting started guide: remove dollar signs for better cut-and-paste

[jak78]

Motivation

When I cut and paste command lines from the getting started guide, I get a dollar sign at the beginning of the command line. So the command does not work on the first attempt. I feel a bit annoyed about that. For a bit more comfort, I suggest we remove this dollar sign.

Modifications

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Verifying this change

• Make sure that the change passes the CI checks.

This change is about documentation.

Does this pull request potentially affect one of the following parts:

If yes was chosen, please highlight the changes

• Dependencies (does it add or upgrade a dependency): (yes / no)
• The public API: (yes / no)
• The schema: (yes / no / don't know)
• The default values of configurations: (yes / no)
• The wire protocol: (yes / no)
• The rest endpoints: (yes / no)
• The admin cli options: (yes / no)
• Anything that affects deployment: (yes / no / don't know)

Documentation

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[github-actions]

The pr had no activity for 30 days, mark with Stale label.

[tisonkun]

Closed as stale. IIRC the getting started guide is rewritten.