Merge stable into master

[MoonlightSentinel]

This should finally unblock dlang/dmd#11027

[dlang-bot]

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Bugzilla references

Auto-close	Bugzilla	Severity	Description
✓	20748	regression	Deprecation for assert using shared type and checkaction=context
✓	20750	minor	checkaction=context segfaults for null references

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 "master + druntime#3046"