Generic trait: type of a method parameter in an abstract method is not specified

[mxr576]

Bug report

I was experimenting with generic traits and it looks like I found a bug, see works() vs doesNotWork() methods.

Code snippet that reproduces the problem

https://phpstan.org/r/465f4f45-2dc7-4406-b82c-a21926d1bdc5

Expected output

57 Dumped type: int

and there is no missingType.parameter error.

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[ondrejmirtes]

Essentially a duplicate of #10914