upgrade finagle-mysql to 21.8.0 and separate scala 2.11 library dependencies (#2179)
upgrade finagle-mysql to 21.8.0 and separate scala 2.11 library dependencies (#2179)

* upgrade finagle-mysql to 21.6.0

* separate finagle-mysql version based on scala version

* upgrade finagle-mysql to 21.8.0

Co-authored-by: Juliano Alves <15fd09e5d4ca6476084bc6322bade1c0eb2f8628@gmail.com>
getquill/quill