Fix Issue 21183 - schwartzSort does not strip const

[MoonlightSentinel]

Fixed by using the unqualified type if possible

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	21183	minor	schwartzSort does not strip const

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 + phobos#7602"

[wilzbach]

Feel free to merge once CI is green

[MoonlightSentinel]

Cannot do that (got no power here).
Anyway, BuildKite will be green once ba02646 is merged into stable.

[wilzbach]

Cannot do that (got no power here).
Anyway, BuildKite will be green once ba02646 is merged into stable.

Yeah we should cherry-pick that one.