Documentation: Lack of consistency/clarity in code sections

[migueldivo]

Docs page: https://juju.is/docs/juju/set-up--tear-down-your-test-environment

Docs source: https://discourse.charmhub.io/t/set-up-tear-down-your-test-environment/13403

Issue: There is a lack of consistency in the way command lines are being displayed throughout the page. Some command lines follow the convention of using '$' to indicate its a command line, but other instances either have nothing to show its a command line, or uses a '#' which means its a comment rather than an action the user should do.

Below are some examples where this is present throughout the page. Command lines should be consistently represented with the '$' to allow users to know what are command lines and what are comments/session sample outputs.

Example that follows standard of using '$' for CLI inputs

Example that does not follow '$' standard, either does not include '$' or uses a '#' which makes a comment