Fix Issue 22801 - Can't return address of return ref parameter from constructor

[dkorpel]

This allows returning return ref parameters by assignment to the first parameter again. Note that this doesn't perform the associated lifetime transfer yet, dmd never did this, and I'm still figuring out how to ask checkAssignEscape to check by ref and not by value.

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	22801	regression	[REG 2.099.0-beta.1] Can't return address of return ref parameter from constructor

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#13699"