audio/ncspot: update to 1.2.1

Changelog for 1.2.0 : https://github.com/hrkfdn/ncspot/releases/tag/v1.2.0
Changelog for 1.2.1 : https://github.com/hrkfdn/ncspot/releases/tag/v1.2.1

Major changes:

• Switch to OAuth2 login mechanism
• Uses librespot 0.5.0 which containts many bugfixes
• Update librespot to 0.6.0