Mla 5473 leave site change

[PeterChaplin]

See https://github.com/qcode-software/mla/issues/5473

Testing

• Ran concatenated code on mla-erp dev
• Enter customer page orders tab and navigate away (unwanted dialog did not appear)
• Enter orders tab, make a change but do not save, attempt to navigate away (dialog appears as expected)
• Save a change, navigate away (change saves correctly, dialog does not appear)

[bvw]

What was the history behind this change?

[PeterChaplin]

In relation to https://github.com/qcode-software/mla/issues/5473
When a cell of type "bool" is given focus, the editor is initialised with the cell contents. This is triggering the editorValueChange event, which marks the row as dirty, which sets up the dbGrid onbeforeunload handler. When the user goes to navigate away, they get a "Leave Site?" dialog, despite not having made any changes.
Other editor types do not have this behaviour, and only fire an editorValueChange event when the user changes the value of the input, not on initial load.
I believe that this editor should do the same, and that the existing behaviour is a bug.