feat: deprecate autocomplete appropriate check

[clottman]

Deprecates autocomplete-appropriate

Closes issue: #2912

[straker]

I talked to Wilco and he mentioned that we should also remove the check from the rule metadata as well. Sorry about that.

[clottman]

@straker I'm not sure what you mean by that, would you mind being more specific?

I did notice looking at some other deprecated checks that the impact for the others was 'minor' - it makes sense to me that a deprecated check shouldn't be a severe impact, so I made that change. Can reverse it if that was the wrong call.

[clottman]

Ah I think I figured it out! :D

[straker]

Sorry missed the first question. Yes you removed it correctly. As for the impact change I don't think we should do that as the impact is based on user testing. The tests will also need to be updated with the removal of the check as those failures will no longer fail.

[WilcoFiers]

Reviewed for security.