refactor: add warning that substitute does not update events

Author: AayushSabharwal

src/systems/abstractsystem.jl

@@ -2113,6 +2113,10 @@ end
 
 keytype(::Type{<:Pair{T, V}}) where {T, V} = T
 function Symbolics.substitute(sys::AbstractSystem, rules::Union{Vector{<:Pair}, Dict})
+    if has_continuous_domain(sys) && get_continuous_events(sys) !== nothing ||
+       has_discrete_events(sys) && get_discrete_events(sys) !== nothing
+        @warn "`substitute` only supports performing substitutions in equations. This system has events, which will not be updated."
+    end
     if keytype(eltype(rules)) <: Symbol
         dict = todict(rules)
         systems = get_systems(sys)