Hi,
Auto-Generate Web Part Title: A generated title that includes the name of the Report Viewer Web Part plus the name of the report, separated by a dash. If the report does not have a title, the report file name is used. The title is visible when you add a
Web Part to a page. If this check box is selected, the title will be generated each time the page is refreshed.
So, this is the default behavior. there is no out of box way to realize it.
I think you can uncheck this option and use a general name as an alternative since user can see the title from the connected web part.
Regards,
Seven