Fab Always visible, even when modal open

### Description

I wanted to enable fab component to be displayed and accessible even when modal was open

### CodeSandbox/Snack link

https://codesandbox.io/s/distracted-lovelace-6nylmu

### Steps to reproduce

1. Create a Modal
2. Create a fab
3. place them on the same screen and open modal

1) On ios you'd see that fab is available regardless modal being open or closed
2) On android fab buttons are covered by the modal and cannot be pressed

### NativeBase Version

3.4.13

### Platform

- [X] Android
- [ ] CRA
- [ ] Expo
- [ ] iOS
- [ ] Next

### Other Platform

_No response_

### Additional Information

I tried elevation and zIndex definitions for theme, setting them as styles, but nothing worked. What do you suggest I do as a workaround?