bugfix - Adds a null check before building TrackLoveRequest (fix #57)

[jesseward]

Summary

As reported in #57 , attempts to "love" a track that does not include ID3 metadata, the plugin crashes with an unhandled exception (System.InvalidOperationException: Sequence contains no elements).

This change adds a null check before building the TrackLoveRequest and returns early if required metadata is not present.

This change also

• cleans up the devcontainer to add sshd
• Adds an additional mp3 file without id3 metadata
• Moves example.mp3 test data to appropriate directory structure, for rich metadata scraping when working in the devcontainer.
• fix logging string formatting within LoveTrack(..)

Related

• Closes Plugin crashes Jellyfin when trying to sync favourited track that has no metadata #57