Fix issue 20063 - Patch closure variables when converting expressions to delegates

[SSoulaimane]

Issue 20063.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20063	regression	compiler segfaults on passing templates expression to lazy val

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#10196"

[PetarKirov]

BTW, one should be careful when using foreach (; 0 .. max) and changing the max inside the loop, as the emitted code caches it:
https://run.dlang.io/gist/run-dlang/b0b40d58474fb7c35b22803b2432c02f?compiler=dmd

[SSoulaimane]

Yes, I notice that, but the code here breaks immediately after remove() is called.