duplicate entries in resume list

[AndroidFactoryDE]

System:

• RPI4, 4GB, Boot from Samsung USB Stick 128GB
• MuPiHAT

Software:

• MuPiBox Image 4.0.4

Current behavior:

• the resume list contains duplicate entries from the same album

Expected behavior:

• the resume list contains only one entry for the same album

Appendix:

• resume.json (source: /home/dietpie/.mupibox/Sonos-Kids-Controler-master/server/config/resume.json)