Update multimedia/emby-server to latest upstream release 3.0.5597.1.

Changes this release:

• Improve Xbox One Dlna
• Episode metadata getting lost after upgrading video file
• Video Ref frame count not being recorded
• Live TV not working in Safari
• PlayTo not working with MediaMonkey (this fix may benefit other DLNA media players)
• Safari "Add to Homescreen" feature not hiding address bar

PR: 199791
Submitted by: Ben Woods (maintainer)