Description of problem

When importing a duplicate questionnaire, it shows a popup with the message:

Version-Release number of selected component (if applicable)

MTA 7.0.3 

How reproducible

Always

Steps to Reproduce:

1. Navigate to Assessment questionnaires page
2. Click on import questionnaire
3. Select a questionnaire to import
4. Click to import another questionnaire, and select the same questionnaire again

Actual results

The following popup notification is displayed

Expected results

A proper notification should be displayed indicating the questionnaire already exists e.g.

UNIQUE constraint failed