Fix 22300 - Use reinterpreting cast for shared types during CTFE

[MoonlightSentinel]

Using the same method for compile- and runtime was enabled by
dlang/dmd#13203. Using a reinterpreting cast avoids any potentially
calling into user-defined opCast methods which might reject the cast.

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	22300	regression	[REG 2.098-rc.2] `-checkaction=context` of a `shared` type with an `opCast` fails to compile

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 + druntime#3594"