Cannot clear datepicker

## 🐛 Bug Report
There is no way to clear the datepicker value.

## To Reproduce

Steps to reproduce the behavior:
Set a date, then try to unset it.

## Expected behavior
If I want to have an optional value, then I should be able to clear the value after setting it.

## Link to runnable example or repository (highly encouraged)
See the demos on the documentation website:
https://akveo.github.io/react-native-ui-kitten/docs/components/datepicker/overview#rangedatepicker

## UI Kitten and Eva version
"@ui-kitten/components": "^5.3.1",
"@eva-design/eva": "^2.2.0",

## Environment information

System:
OS: Linux 6.4 Manjaro Linux
CPU: (16) x64 AMD Ryzen 9 6900HS with Radeon Graphics
Binaries:
Node: 16.18.0 - ~/.nvm/versions/node/v16.18.0/bin/node
Yarn: 1.22.19 - /usr/bin/yarn
npm: 8.19.2 - ~/.nvm/versions/node/v16.18.0/bin/npm
npmPackages:
react: 18.2.0 => 18.2.0
react-native: 0.72.3 => 0.72.3