fix issue 20057 - compiler hang on conflicting local and imported template

[ghost]

The regression is on master only and was caused by #10078

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20057	regression	compiler hang on conflicting local and imported template

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 "master + dmd#10194"

[thewilsonator]

Please target stable.

[ghost]

No, the regression is on master only (was caused by #10078)