P2944R3: Comparisons for `reference_wrapper`

[ldionne]

Link: https://wg21.link/P2944R3

• Comparisons for reference_wrapper
• Constrained equality

BEGIN-RST-NOTES
Implemented comparisons for ``reference_wrapper`` only
END-RST-NOTES

[Zingam]

This is partially implemented in:
#88384
I'm assigning this to me for later.
If someone feels like to take it over please feel free to reassign it.

[miroslavavramov]

I want to join in your project. I install ubuntu virtual machine in my PC an I am ready to start. Please connect with me on miroslavavramovster@gmail.com