Point manager should not open when the point picking dialog is open as it already has a point manager

[StephenNneji]

This issue is a feature report

When measurement points are added from file and the point picking dialog is opened, the point manager in the point picking dialog should be used instead of opening a new one

• What is the current behaviour?

A new point manager is opened and replaces the point picking dialog

• What is the expected behaviour?

When measurement points are added from file and the point picking dialog is opened, just show the point manager tab of the point picking dialog