fixed docs

Author: torfjelde

docs/src/api.md

@@ -81,8 +81,8 @@ AbstractMCMC.chainsstack
 
 To make it a bit easier to interact with some arbitrary sampler state, we encourage implementations of `AbstractSampler` to implement the following methods:
 ```@docs
-AbstractMCMC.parameters(state)
-AbstractMCMC.setparameters!!(state, parameters)
+AbstractMCMC.parameters
+AbstractMCMC.setparameters!!
 ```
 and optionally
 ```@docs