fix: fix isvarkind for Symbolics.Arr

Author: AayushSabharwal

src/variables.jl

@@ -90,7 +90,7 @@ struct Equality <: AbstractConnectType end # Equality connection
 struct Flow <: AbstractConnectType end     # sum to 0
 struct Stream <: AbstractConnectType end   # special stream connector
 
-isvarkind(m, x::Num) = isvarkind(m, value(x))
+isvarkind(m, x::Union{Num, Symbolics.Arr}) = isvarkind(m, value(x))
 function isvarkind(m, x)
     iskind = getmetadata(x, m, nothing)
     iskind !== nothing && return iskind