Make --dry-run flag consistent across rubygems commands

[bronzdoc]

Description:

closes #3866

Make --dryrun flag consistent across Rubygems commands

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I will abide by the code of conduct.

[nobu]

GNU make also provides -n, --just-print, --dry-run, --recon.

[duckinator]

@bronzdoc on master, --dryrun is only used once across Bundler and RubyGems, whereas --dry-run is used twice and seems to be the norm elsewhere. Given that, I'd rather see gem cleanup switched to use --dry-run with --dryrun as a backwards-compatible alias, because it would make the whole RubyGems+Bundler pair more internally consistent and more consistent with other software.

[deivid-rodriguez]

I agree with @duckinator!

[deivid-rodriguez]

@bronzdoc Do you agree with @duckinator's suggestion? Are you planning to update the PR with that approach?

[bronzdoc]

Dang, I totally forgot about this... I agree!

Will Work on Rubygems later today and will update this PR sorry for taking that long fellas

[deivid-rodriguez]

I saw that the --update-sources option to gem install passes a :Deprecated first argument to add_option and the consequence of this is that the option appears under a separate group called Deprecated Options in gem install --help output. Maybe it's a good idea to do it here too?

[bronzdoc]

Should I deprecate -d to and stick to just -n since im already touching those flags in this PR?

[deivid-rodriguez]

Not sure 🤔. I think we can leave it as it is, and remove it if it confuses someone, but I don't have an issue with deprecating it either.

[bronzdoc]

Ok, sounds good

[duckinator]

This looks good to me!

[deivid-rodriguez]

CI failure is unrelated (possibly fixed by #3850), so merging.

Thanks @bronzdoc!