Advance deprecation of delete expressions, class allocators, class deallocators: Error

[JinShil]

Documentation update to accompany dlang/dmd#9666

[dlang-bot]

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[jacob-carlborg]

What’s the change, trailing whitespace?

[JinShil]

What’s the change

If you look at https://dlang.org/deprecate.html you'll see the "Error" column is blank. After this is pulled, it will be populated with the DMD version number in which dlang/dmd#9666 appears. Right now I'm trying for 2.086, but I may have to update this PR to 2.087 if I can't get it done on time.