Migrate tools/toolsbeta grid to Debian Buster since Stretch is deprecated. This is mostly just adding Buster queues, but then Stretch queues need to go away.
[x] make sure exec grid works
[] make sure webgen grid works -- mostly working, but double-check blocked by {T301117}
[] make sure weblight grid works -- mostly working, but double-check blocked by {T301117}
[x] make sure jsub uses `stretch` as default release https://gerrit.wikimedia.org/r/plugins/gitiles/labs/toollabs/+/refs/heads/master/jobutils/bin/jsub#727
[x] make sure webservice uses `stretch` as default release https://gerrit.wikimedia.org/r/plugins/gitiles/operations/software/tools-webservice/+/refs/heads/master/scripts/webservice#239
[] verify usrmerge stuff
[] make sure cron servers work in the new setup (specially with usrmerge stuff)
[] elaborate timeline and release notes for the community in https://wikitech.wikimedia.org/wiki/News/Toolforge_Stretch_deprecation
[] make sure the release notes ask folks to migrate to k8s
[] make sure the release notes include clear information about the future of the grid
About the migration itself, this will be handled by (@komla):
[] review migration instructions, make sure we document common pitfalls and errors.
[] create migration timeline.
[] create migration communication plan.
[] make sure controls are in place so we have visibility about how the migration is proceeding (https://sge-status.toolforge.org/ and friends)
[] as an alternative to the stretch->buster migration, we would like to offer the alternative to migrate to k8s directly. Create wikitech docs for toolforge-jobs. See https://phabricator.wikimedia.org/T285944
[] create plan for tools that don't migrate