[ConfigTransformer] `FQCN::method` static factories are transformed to syntax error

[Wirone]

Initially reported here. I was able to find that such YAML usage results with syntax error in PHP format:

services:
  foo:
    factory: Foo\Bar::baz

- ->factory([service(Bar::class),·'baz']);
+ ->factory([Bar::baz]);

Basically output file has syntax error because there is no such thing like Bar::baz. On the other hand, Foo\Bar::baz works properly in YAML, it's resolved to proper class/method.

Expected behavior

Factories' definitions are transformed properly, without syntax error.

[TomasVotruba]

We'll need a failing test fixture for this one.