doc/cephadm: small improvements to troubleshooting.rst

doc/cephadm: small improvements to troubleshooting.rst

Programmatically add fsid to example script instead of telling user to add it.
Re-organize CLI example and output that was all on the same line.

Use title case consistently in section titles.
Use the standard style section title levels markup and preceding newlines.
Use double backticks consistently for literal strings.
Improve markup. Improve prompt usage.

Fix word capitalization and minor changes to words.

Delete spaces at end of lines.

Signed-off-by: Ville Ojamo <14869000+bluikko@users.noreply.github.com>