Remove unused method from prior string validation

cel/decls.go

@@ -353,43 +353,3 @@ func ExprDeclToDeclaration(d *exprpb.Decl) (EnvOption, error) {
 		return nil, fmt.Errorf("unsupported decl: %v", d)
 	}
 }
-
-func typeValueToKind(tv ref.Type) (Kind, error) {
-	switch tv {
-	case types.BoolType:
-		return BoolKind, nil
-	case types.DoubleType:
-		return DoubleKind, nil
-	case types.IntType:
-		return IntKind, nil
-	case types.UintType:
-		return UintKind, nil
-	case types.ListType:
-		return ListKind, nil
-	case types.MapType:
-		return MapKind, nil
-	case types.StringType:
-		return StringKind, nil
-	case types.BytesType:
-		return BytesKind, nil
-	case types.DurationType:
-		return DurationKind, nil
-	case types.TimestampType:
-		return TimestampKind, nil
-	case types.NullType:
-		return NullTypeKind, nil
-	case types.TypeType:
-		return TypeKind, nil
-	default:
-		switch tv.TypeName() {
-		case "dyn":
-			return DynKind, nil
-		case "google.protobuf.Any":
-			return AnyKind, nil
-		case "optional":
-			return OpaqueKind, nil
-		default:
-			return 0, fmt.Errorf("no known conversion for type of %s", tv.TypeName())
-		}
-	}
-}