Our 4 MediaWiki clusters, `application`, `api`, `jobrunners/videoscalers`, `parsoid` need to be migrated to Debian Buster.
Provisional plan for the migration:
[] Upgrade all current **stretch** servers to ICU 63 T264991
[] Rebuild all our php-7.2 packages for Debian Buster (buster-wikimedia)
[] php7.2-cli
[] php7.2-common
[] php7.2-curl
[] php7.2-dba
[] php7.2-fpm
[] php7.2-gd
[] php7.2-gmp
[] php7.2-mysql
[] php7.2-opcache
[] php7.2-phpdbg
[] php7.2-readline
[] php7.2-xml
[] Build missing packages for Buster
[] Fix puppet code to support Buster
[] Reimage mwdebug1001 to buster OR introduce mwdebug1003, so not to mess with development testing
**Q3**
[] Reimage `api` canaries
[] Reimage `appserver` canaries
[] Reimage `parsoid` canaries
[] Reimage `jobrunner/videoscaler` canaries
[] Mark all special servers in our clusters (scap proxies, mcrouter proxies)
[] Reimage All clusters (add ertherpad link with list of servers)