[Vimeo] Adds a specific hint for which param to use when a video is password protected

[1RedOne]

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Description of your pull request and other information

With Vimeo vids, we see lots of people raising issues (like this one, #15980 ) when they are trying to provide a -Password param, which is the wrong choice for the Vimeo domain for password protected videos. If a user tries to download a password protected video and provides no password, there is a UI hint in the error message for that...but not if they use the patently wrong param like this.

This patch adds a specific hint on the Vimeo wrong username/password scenario to mitigate this in the future, like #15980

[dstftw]

If user downloads a password protected video or an album without providing a password he will be explicitly prompted about that. No need to create a mess in unrelated places.

[1RedOne]

Check out the related issue, people have mistakenly thought that -Password was the way to go (myself included). In one of those threads, you yourself had to direct people on the right param to use.

Why not display a hint to the user in such a case?

[dstftw]

Why do you even think writing this hint in another place will make any difference? If one does not bother reading output he won't read it from here either.
mistakenly thought is a really bad excuse. What if one'd mistakenly thought that --username is the way to go for custom user agent? Or similarly --password for --ap-password? Or more terminal scenarios? Make another additions to hint for these cases? What about another extractors? Add these hints to all other extractors with authentication? No, never happening.