.credo.exs: Clear removed tests

.credo.exs

@@ -126,10 +126,6 @@
 
         # Deprecated checks (these will be deleted after a grace period)
         {Credo.Check.Readability.Specs, false},
-        {Credo.Check.Warning.NameRedeclarationByAssignment, false},
-        {Credo.Check.Warning.NameRedeclarationByCase, false},
-        {Credo.Check.Warning.NameRedeclarationByDef, false},
-        {Credo.Check.Warning.NameRedeclarationByFn, false},
 
         # Custom checks can be created using `mix credo.gen.check`.
         #