PRs for 4.4 are waiting for reviews

@ozornick Oh, thank you for checking!

1. Why BC? What will be broken? It just adds a new method.

2. Oh, because your code was wrong. 
"Config\App::class" means "\Some\Where\Config\App::class" if the file has "namespace Some\Where;".
And even if it does not exist, v4.3.x looks for "App" (short classname) in "\Config" (because of preferApp).
But in 4.4, the framework looks for "\Some\Where\Config\App::class" because you specify class with the namespace,

See https://github.com/codeigniter4/CodeIgni...-factories

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