Fix Issue 20833 - Template members prevent __traits(getOverloads) from working properly

[rmanthorpe]

There was no handling for DotTemplateExpressions so declaring a template overload before a regular overload prevented it from finding any overloads.

Fixes a regression introduced by #8195.

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20833	regression	Template members prevent __traits(getOverloads) from working properly

Testing this PR locally

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

dub run digger -- build "stable + dmd#11295"