Fix change event

[yuriy-fix]

Description of the issue:
On text-change we are setting the __debounceSetValue which will change the value after 200ms. On focusout we are comparing __lastCommittedChange and current value and if they are not the same we are dispatching the change event.

But in case when the focusout will occur before 200ms timeout, debouncer will be flushed and on the focus check hasFocus() in the _valueChanged observer it will set the __lastCommittedChange to be the current value. It will lead to not dispatching change event.

The test are now using blur before focusout in order to properly check Quill's hasFocus