update cluster deployment steps to avoid --background

[taroface]

Ryan Kuo (taroface) commented:

Steps to start a cluster at e.g. https://www.cockroachlabs.com/docs/stable/start-a-local-cluster.html should be updated to:

• Have users start each node in the foreground. Per @bdarnell, we are discouraging the use of --background and most examples in the docs should start each node in a new terminal.
• Remove use of cockroach quit to stop nodes. Instead, use instructions here as documented in revise node decommissioning guidance and semantics #7304.
• Possibly deemphasize the use of --listen-addr per this thread (but this may mean broader changes).

Jira Issue: DOC-523

[jseldess]

For future triage and prioritization, @taroface and @johnrk.