code: function createCheckDefaultValue(fieldDefinition, fieldName) {
    const defaultValue = fieldDefinition.defaultValue;
  
    // -----------------------------------------------------------------------
    // Set default value
    // -----------------------------------------------------------------------
    return function (content) {
  
      const valueToCheck = content[fieldName];
      // If the value is defined, we need to check it
      if (valueToCheck === undefined || valueToCheck === null) {
        if (defaultValue !== undefined) {
          content[fieldName] = defaultValue;
        }
      } else {
        if (Array.isArray(valueToCheck)) {
          valueToCheck.forEach(function (item, idx, arr) {
            if (item === undefined || item === null) {
              arr[idx] = defaultValue;
            }
          });
        }
      }
    };
  }
docs: Set the default value if no value is there
  @param fieldDefinition The field_definition for this field.
  @param fieldName The name of the current field
  @return checks A list of checks to be perfomred