P2404R3: Move-only types for `equality_comparable_with`, `totally_ordered_with`, and `three_way_comparable_with`

[ldionne]

Link: https://wg21.link/P2404R3

BEGIN-RST-NOTES
Implemented as a DR in C++20.
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[frederick-vs-ja]

I modified the issue description to say "Implemented as a DR in C++20.".

（Perhaps the script will see this.)