Number input returns empty value when user enters `Dot`

### Describe the bug
When user enters decimal numbers `eg: 1.5`, the onChange callback of NumberInput component intermittently returns empty value.

This is causing issue for Set-number fields which was implemented in MC-frontend (experimental component).
The `Set` fields works based on total number of values present and ignoring any empty values. When the user inputs `.` (dot) then the `onChange` returns empty value which is causing the Number input in the UI to disappear.

https://commercetools.atlassian.net/browse/PDM-5

JFYI: @bradd123 & @ismaelocaramelo have some ideas for how it could be done by UI Kit.

### Steps To Reproduce

- Goto [product detail page](http://localhost:3001/test-with-big-data-44/products/76a721bf-39ba-421f-825e-21d280420850) which has set-number (eg: Attribute SET-NUMBER SameForAll )
- Click on the `plus` icon to add a new number input
- Enter a floating number with dot (eg: 2.5)
- Notice the newly added number input disappeared

### Expected behavior

- If possible, I would expect the `onChange` to return the dot along with number `1.`
- If that is not possible then it would be better if we append zero and return `1.0`
- If you have any other solution to this issues, please let me know.