[php-src] Issue #9398: Attempting to alias keywords results in a cryptic Parse error

Issue: https://github.com/php/php-src/issues/9398 Author: Girgias ### Description This issue is most notable with the `array` keyword as it is also a built-in type name. Indeed trying to alias `int`: ```php <?php use int as I; ``` Parses just fine (however it is impossible to actually use I as a type declaration as you would get the following error `Fatal error: Cannot use 'int' as class name as it is reserved in /in/nNOgL on line 5` (see https://3v4l.org/nNOgL) which is its own mess that we might want to catch early) However, with `array` (https://3v4l.org/fWrTK): ```php <?php use array as a; ``` We get the following error message: ``` Parse error: syntax error, unexpected token "array" in /in/F6SlE on line 3 ``` I don't even know if this is actually fixable as this seems like some parser shenanigans. ### PHP Version PHP 8.0.22 - master ### Operating System _No response_