Ensure indeterminate progress dialogs centred on screen before visible (#14024)
Summary of the issue:
The NVDA update checker and other indeterminate progress dialogs become visible before they are centred on screen.
Description of user facing changes
Indeterminate progress dialogs used in NVDAs GUI are centred before they become visible, and do not jump across the screen.
Description of development approach
Change the order of raise and centre on screen