Add shorthand for --tail option

[horpto]

I chose -n shorthand as it's similar with linux tail command.

- What I did

- How I did it

- How to verify it

- Description for the changelog

Add shorthand -n for --tail option

- A picture of a cute animal (not mandatory but encouraged)

[codecov-commenter]

Codecov Report

Merging #2646 into master will not change coverage.
The diff coverage is 0.00%.

@@           Coverage Diff           @@
##           master    #2646   +/-   ##
=======================================
  Coverage   58.13%   58.13%           
=======================================
  Files         295      295           
  Lines       21194    21194           
=======================================
  Hits        12321    12321           
  Misses       7966     7966           
  Partials      907      907           

[thaJeztah]

Thanks for contributing ; I'm ok with this change (name is consistent with -n on docker ps), but want to double check with some other maintainers.

Could you also;

• update the usage output in the docs here; https://github.com/docker/cli/blob/master/docs/reference/commandline/logs.md
• update the bash completion script in https://github.com/docker/cli/tree/master/contrib/completion/bash to have the new flag added?

Let me know if you need help with that

[horpto]

@thaJeztah thanks for reply. I found other place with logs.

[albers]

Completion LGTM, thanks for the contribution.

[thaJeztah]

LGTM

thank you!

[thaJeztah]

@cpuguy83 @silvin-lubecki looking good?

[silvin-lubecki]

LGTM, thanks @horpto 👍

[thaJeztah]

Let's get this one merged 👍