time-picker mode with setDateOnMenuClose sets modelValue to start-time even if nothing entered

[jacobg]

Describe the bug
Thank you for recently adding the setDateOnMenuClose config option. It's very useful. As expected, when using date picker if nothing is typed or selected in the date picker, then closing the menu does not set modelValue. However in time-picker mode, it does set the modelValue to start-time even though no time was typed or selected. Note that start-time is still useful to display an initial value in the selector (e.g., 00:00 instead of default current time), but not expected to be used if user doesn't select it or type anything.

To Reproduce
Steps to reproduce the behavior:

1. Go to https://stackblitz.com/edit/vuepic-vue-datepicker-pkxtkx?file=src%2Fcomponents%2FPlayground.vue
2. Click on input to open picker menu.
3. Clock outside menu to close it.

Expected behavior
Neither modelValue nor input box should be set with value.

Actual behavior
It is setting the value to the start-time value.

Screenshots
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Desktop & mobile (please complete the following information):

• Browser [e.g. chrome, safari]
• Library version [e.g. 3.0.0]