Reproduce autoloader bug

[staabm]

this test demonstrates how PHPStan analyzes code differently than it would happen at runtime.

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runtime: run php real-world.php you see the program runs, without the custom autoloader of e2e/bug-12972b/autoloader.php beeing invoked. all involved classes are autoloaded by the composer class loader. the custom class loader is not invoked for \other12972\MyClass::class.

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static analysis time: run ../../bin/phpstan analyze

you see PHPStan invokes the custom class loader for class \other12972\MyClass::class, which does not happen at regular runtime. the composer class loader is not invoked for \other12972\MyClass::class (like it is at runtime).

because of the difference in autoloading functions order in runtime vs. analysis time we see errors which cannot happen at runtime - see https://github.com/phpstan/phpstan/issues/12972