fixed App crashes when trying to change radius on avatar

[kiranraj20]

fixed #2109
The value is not present if you click on the same element so the function ".toString()" throws an error as the values are not present.
The simple solution is to check whether the value is present or not and the function should be called only when the value is present.

[DemaPy]

Problem lies in handler, this is one duplicated actually.
See here: #1978

[DemaPy]

@googleknight corrected it already and waiting for approval.

  const onBorderRadiusChange = (value: string) => {
    if (!value) return;
    setValue("basics.picture.borderRadius", stringToBorderRadiusMap[value as BorderRadius]);
  };