Clear does not reset/clear the underlying viewdate

[ZTHawk]

Prerequisites

• I have searched for duplicate or closed issues.
• I have validated my setup against the latest version on StackBlitz.
• I have read the contributing guidelines.
• I understand that only sponsored issues will be worked on and that if I wish to sponsor an issue, I will contact the owner FIRST.

Describe the issue

When clicking on the clear button then the underlying viewDate object still has the last selected date. Only the UI is cleared.

1. Select a date
2. Clear the date using the clear button
3. Click "test" button to show the content of viewDate

I am expecting to see an empty value.

StackBlitz fork

https://stackblitz.com/edit/tempus-dominus-v6-simple-setup-azfauzxx?file=index.html,index.js

What operating system(s) are you seeing the problem on?

Windows

What browser(s) are you seeing the problem on?

Firefox

What version of are you using? You can find this information from the sample StackBlitz.

v6.10.4

What your browser's locale? You can find this information from the sample StackBlitz.

en-US