Regression: `replace` broken

[TorkelE]

MWE:

using Symbolics
@variables t X(t)
Symbolics.replace(X, X =>1)

gives a

ERROR: MethodError: no method matching operation(::Int64)

Closest candidates are:
  operation(::SymbolicUtils.Code.Func)
   @ SymbolicUtils ~/.julia/packages/SymbolicUtils/qyMYa/src/utils.jl:224
  operation(::SymbolicUtils.Code.AtIndex)
   @ SymbolicUtils ~/.julia/packages/SymbolicUtils/qyMYa/src/utils.jl:224
  operation(::SymbolicUtils.Code.DestructuredArgs)
   @ SymbolicUtils ~/.julia/packages/SymbolicUtils/qyMYa/src/utils.jl:224
  ...

Stacktrace:
 [1] (::SymbolicUtils.Rewriters.Walk{…})(x::SymbolicUtils.BasicSymbolic{…})
   @ SymbolicUtils.Rewriters ~/.julia/packages/SymbolicUtils/qyMYa/src/rewriters.jl:205
 [2] #_replace#24
   @ ~/.julia/packages/Symbolics/Eas9m/src/rewrite-helpers.jl:38 [inlined]
 [3] _replace(expr::SymbolicUtils.BasicSymbolic{Real}, rules::Pair{Num, Int64})
   @ Symbolics ~/.julia/packages/Symbolics/Eas9m/src/rewrite-helpers.jl:32
 [4] replace(::Num, ::Pair{Num, Int64})
   @ Symbolics ~/.julia/packages/Symbolics/Eas9m/src/rewrite-helpers.jl:16
 [5] top-level scope
   @ ~/Desktop/Julia Playground/tmp/playground.jl:8
Some type information was truncated. Use `show(err)` to see complete types.

this used to work and there are tests for this, but seems to have slipped past CI