Confusing use of ticks in FS0064 warning.

[majocha]

See the real life situation here #18808

One type argument is 'TRequest, the other 'TRequest'

The first impression is that the warning message adds it's own ticks without rhyme or reason:

This construct causes code to be less generic than indicated by the type annotations. The type variable 'TRequest' has been constrained to be type ''TRequest'

It's also not correct in the sense that the second part is not actual type but a type variable.