NumberValidatorError: static class -> enum

Author: LahaLuhem

lib/src/validators/number_validator_error.dart

@@ -1,6 +1,6 @@
-class NumberValidatorError {
-  static const String nullValue = 'nullValue';
-  static const String invalidDecimals = 'invalidDecimals';
-  static const String unsignedNumber = 'unsignedNumber';
-  static const String invalidNumber = 'invalidNumber';
+enum NumberValidatorError {
+  nullValue,
+  invalidDecimals,
+  unsignedNumber,
+  invalidNumber;
 }