mbsync: upgrade to mbsync 1.2.x
mbsync: upgrade to mbsync 1.2.x

Some days ago, mbsync 1.2.x has migrated to Debian testing. This
requires to enable encryption with `SSLType` instead of  the now
deprecated `UseIMAPS`.

It also appears mbsync doesn't play well with dovecot using the PLAIN
authentication method. The deprecated `LOGIN` method does work however.
I should investigate this further.
https://sourceforge.net/p/isync/mailman/message/32955053/

paretje/dotfiles,paretje/dotfiles,paretje/dotfiles,paretje/dotfiles,paretje/dotfiles