[macOS] bundle-identifier is still "com.jelleglebbeek.youtube-dl-gui", colliding with upstream

[core-code]

the CFBundleIdentifier in the Info.plist file should be changed to an unique value, instead of colliding with the upstream vendors name ( com.jelleglebbeek.youtube-dl-gui )

[StefanLobbenmeier]

Sure I can change it to my name. Is there a specific requirement for this / an issue you are facing or just for tidiness?

[core-code]

for one, any third party updater will confuse the app with the original because it is indistinguishable