Fix issue 20059 - mismatched function return type inference should gi…

[thewilsonator]

…ve location of inferred type

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20059	enhancement	mismatched function return type inference should give location of inferred 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 "master + dmd#10190"

[PetarKirov]

Thanks!