[Issue 19303] hasMember fails to recognize member (interaction with mixin template)

[d-bugmail at puremagic.com]

https://issues.dlang.org/show_bug.cgi?id=19303

--- Comment #2 from Eduard Staniloiu <edi33416 at gmail.com> ---
What is even weirder, if you define your own `hasMember` wrapper, that works
just fine with the initial definition of Port

```
enum hasM(T, string name) = __traits(hasMember, T, name);

static assert(hasM!(P, "ElementType")); // ok
```

As reflected by https://run.dlang.io/is/pKYL9B

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