fix: remove partially copied code comment (#5070)

Author: nomeata

src/Lean/Meta/Tactic/Simp/SimpTheorems.lean

@@ -483,7 +483,6 @@ def SimpTheorems.addDeclToUnfold (d : SimpTheorems) (declName : Name) : MetaM Si
         if i + 1 = eqns.size then 0 else 1
       else
         100 - i
-      -- We assign very low priority to equational le
       d ← SimpTheorems.addConst d eqn (prio := prio)
     /-
     Even if a function has equation theorems,