fix issue 19950 - access violation at compile time, possibly via template constraint and alias interaction

[ghost]

It looks like it was a problem of bad logic with error gagging. The function does not emit more errors when going to Lnomatch so there's no need to mind about the previous gagging state.

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	19950	normal	access violation at compile time, possibly via template constraint and alias interaction

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#10195"