Music Discs (Beta Mix)

Replaces Music Disks with their Beta Mixes if they are full length.
Only changes audio.

List of discs and weather or not they are changed:

• 13 [X]
• Cat [✓]
• Blocks [X]
• Chirp [X]
• Far [X]
• Mall [✓]
• Mellohi [X]
• Stal [X]
• Strad [X]
• Ward [X]
• 11 [X]
• Wait [X]
• Pigstep [X]
• Otherside [X]
• 5 [X]
• Relic [X]