Fixer that converts to get_debug_type() under PHP8

[keradus]

ref symfony/symfony#35945

requested by @nicolas-grekas

[derrabus]

To brainstorm this, what kind of expression would that fixer convert to get_debug_type()? This tenary expression probably:

is_object($var) ? get_class($var) : gettype($var)

Anything else?

[kubawerlos]

Separate get_class($var) or gettype($var) too.