fix doctests too

Author: penelopeysm

src/simple_varinfo.jl

@@ -39,7 +39,7 @@ julia> rng = StableRNG(42);
 julia> # In the `NamedTuple` version we need to provide the place-holder values for
        # the variables which are using "containers", e.g. `Array`.
        # In this case, this means that we need to specify `x` but not `m`.
-       _, vi = DynamicPPL.sample!!(rng, m, SimpleVarInfo((x = ones(2), )), ctx);
+       _, vi = DynamicPPL.sample!!(rng, m, SimpleVarInfo((x = ones(2), )));
 
 julia> # (✓) Vroom, vroom! FAST!!!
        vi[@varname(x[1])]