Use "shell" instead of "shell-session" as language directive in examples

[zupo]

• Makes syntax highlighting more likely to work.
• Less is more.

Also, tell users to use !! to rerun the last command in debug prompt.

[blueracer-io[bot]]

Unit tests performance report: ✅

Everything looks great, carry on!

Branch	Number of tests	Suite duration	Mean test duration
main	19	33.7s[^1]	1771.5ms[^1]
gardening[^2]	19 (0%)	33.5s (0%)	1764.7ms (0%)

[^1]: The median/mean of the previous 4 runs. [^2]: More specifically from commit 4c74ed9260182448f36deb15640b8cb7e5fe8be8 in run #1. [^2]: More specifically from commit 4c74ed9260182448f36deb15640b8cb7e5fe8be8 in run #1.

[domenkozar]

The terminology depends on who is highlighting the code.

shell usually means bash code, while shell-session means a terminal session.

It seems that the most commonly used name for this is console: https://github.com/rust-lang/book/issues/1449

[zupo]

shell usually means bash code, while shell-session means a terminal session.

Huh, in my editor, shell is colored like console, not like bash. I'd have to check how it is on GitHub too.

In any case, I'm perfectly fine with console, have only a slight preference for shell because it's shorter.

[zupo]

GitHub does in fact have shell as an alias for bash, and console for shell session:

• https://github.com/github/linguist/blob/master/lib/linguist/languages.yml#L6204
• https://github.com/github/linguist/blob/master/lib/linguist/languages.yml#L6288

I'll rewrite to console then.

[zupo]

@domenkozar: ready for re-review