fix: documentation of multiset_permutations (#141)

Co-authored-by: inky <[email protected]>

src/permutations.jl

@@ -171,7 +171,7 @@ function Base.length(c::MultiSetPermutations)
 end
 
 """
-    multiset_permutations(m, f, t)
+    multiset_permutations(a, t)
 
 Generate all permutations of size `t` from an array `a` with possibly duplicated elements.
 """