Fix sniff error name in PHPCS error message

[mk-mxp]

In src/Sniffs/ExplainStrictTypesSniff.php we produce a addFixableError() with self::class. This shouldn't be the fully qualified class name, but an identifier unique for the error message like Missing.

This is not a functional problem, only an oddity in case of an error:

FILE: /home/runner/work/php/php/exercises/practice/meetup/.meta/example.php
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FOUND 1 ERROR AFFECTING 1 LINE
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 2 | ERROR | [x] Missing explanation of declaration of strict types.
   |       |     (Exercism.StrictTypes.ExplainStrictTypes.Exercism\Sniffs\StrictTypes\ExplainStrictTypesSniff)
--------------------------------------------------------------------------------
PHPCBF CAN FIX THE 1 MARKED SNIFF VIOLATIONS AUTOMATICALLY
--------------------------------------------------------------------------------

Time: 4.12 secs; Memory: 8MB

The message identifier may be used to configure severity etc. The class name is converted to the dot notation correctly, and our custom message identifier is appended after the last dot. The FQCN here makes the message look broken and does not help.

[tomasnorre]

I think this is already include in the #857 with the commit from @jrfnl

[jrfnl]

It is.

[tomasnorre]

I have closed this as it solved in #857