The package_sparkfun_index.json on the main branch is not compliant with the arduino framework documentation

[jantje]

https://raw.githubusercontent.com/sparkfun/Arduino_Boards/main/IDE_Board_Manager/package_sparkfun_index.json
Has 2 packages both with the same name.
As explained here this is IMHO not compliant with arduino framework documentation
Sloeber/arduino-eclipse-plugin#1681 (comment)