New `≡⟨_⟨` syntax for `≡˘⟨_⟩`?

[pmbittner]

In the Agda standard library, the syntax of ≡˘⟨_⟩ was changed to ≡⟨_⟨. Maybe it should be changed here as well but I am not sure:

agda2hs/lib/Haskell/Law/Equality.agda

Line 59 in fdbebb6

syntax step-≡˘ x y≡z y≡x = x ≡˘⟨ y≡x ⟩ y≡z