fix issue 19708 - Can't use __traits(getAttributes, ...)[...] as a type

[ghost]

The first part of the fix is simply to extract Types from TypeExprs when a TypeTrait returning a TypeTuple contained some .

The second part is more delicate. A flag used by the TypeTraits was not set correctly because the TypeTrait was not directly aliased but wrapper in a TypeNext.

And finally there's a problem with git here. Walter appears as author for some reasons I don' understand.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	19708	normal	Can't use __traits(getAttributes, ...)[...] as a type

Testing this PR locally

If you don't have a local development environment setup, you can use Digger to test this PR:

dub fetch digger
dub run digger -- build "stable + dmd#10143"