DatePicker with "showTimeSelectOnly" is not possible clear the value

[MarcoB89]

Describe the bug
When the datepicker is configured with property "showTimeSelectOnly" it's not possible to clear the value

To Reproduce
Steps to reproduce the behavior:

0. Go to the page 'https://reactdatepicker.com/' and find the "Select Time Only" example (https://reactdatepicker.com/#example-select-time-only)
1. Click on the datepicker
2. Clear the value in the input (backspace or delete on the keyboard)
3. Click outside
4. The previous value reappears in the input

Expected behavior
The datepicker should be cleared, withuout value

Screenshots
Step 1

Step 2

Step 3 and 4

Desktop (please complete the following information):

• OS: Windows 10
• Browser Chrome
• Version 115.0.5790.102 (Official Build) (64-bit)
• Version ReactDatepicker 4.16

Additional context
I tryed in a previous versione of react-datepicker (4.8.0) and it worked, so i think is a regression

[balajis-qb]

Hi @martijnrusschen,

I found the reason behind this issue. Can you please assign this issue to me? I'll work on it

[balajis-qb]

Hi @martijnrusschen ,

I added a fix for the issue - #4336. Kindly review my PR and let me know if any changes required. Thank you