Disable MiMa for 2.12.0-M2.
Disable MiMa for 2.12.0-M2.

fthomas/shapeless,wheaties/shapeless,triggerNZ/shapeless,liff/shapeless,lambdista/shapeless,alexarchambault/shapeless,TomasMikula/shapeless,milessabin/shapeless,clhodapp/shapeless,notxcain/shapeless,khronnuz/shapeless,isaka/shapeless,lukasz-golebiewski/shapeless,roberth/shapeless