Find Any File can remove leftover components of apps that have been deleted. Do the following:
#1 - boot into Safe Mode according to Start up your Mac in safe mode - Apple Support.
NOTE: Safe Mode boot can take up to 10 minutes as it's doing the following;
• Verifies your startup disk and attempts to repair directory issues, if needed
• Loads only required kernel extensions (prevents 3rd party kernel/extensions from loading)
• Prevents Startup Items and Login Items from opening automatically
• Disables user-installed fonts
• Deletes font caches, kernel cache, and other system cache files
#2 - download and run the shareware app Find Any File to search for any files with the application's or the developer's name in the file name. For CleanMyMac software you'd do the following search(es):
1 - Name contains bitdefender
Any files that are found can be dragged from the search results window to the Desktop or Trash bin in the Dock for deletion.
FAF can search areas that Spotlight can't like invisible folders, system folders and packages.
#3 - reboot normally.