[libcxx-commits] [libcxx] [libc++][NFC] Centralize test for support of == and != in ranges (PR #78481)

[Will Hawkins via libcxx-commits]

hawkinsw wrote:

I noticed that these tests were implemented differently in different places throughout the range adapter test code. I hope that this is something that is useful! 

https://github.com/llvm/llvm-project/pull/78481