Fix bug in snoopi_deep: missing copy() on slottypes array

The slottypes array is reused and modified, so we need to make a copy of
it for each inference frame. This was a bug accidentally introduced in #38143

base/compiler/typeinfer.jl

@@ -34,7 +34,7 @@ function _typeinf_identifier(frame::Core.Compiler.InferenceState)
  frame.linfo,
  frame.world,
  copy(frame.sptypes),
- frame.slottypes,
+ copy(frame.slottypes),
  )
  return mi_info
 end