Task to be used to track blockers for the `1.27.0-wmf.12` deployment.
From https://wikitech.wikimedia.org/wiki/Heterogeneous_deployment/Train_deploys , duties are:
[x] 1.1 Create the new branch in gerrit - //Cut on Tuesday Feb 2nd ~ 19:00 UTC//
[ ] 1.2 Remove symlinks to expired branches - //Probably fine now due to Tuesday staging wipe out//
[x] 1.3 Clone new branch - //checkoutMediaWiki had set current to .11. Fixed manually back to .10//
[x] 1.4 Apply security patches - one no more apply, renamed with meaningful suffix
[x] 1.5 Create symlink patch for common/docroot - /w/php and /docroot/static symlinks been migrated to .11. Had to manually fix them to .10
[x] 1.6 Create patches to update wikiversions.json
[x] 1.7 Send staged patches to gerrit for review - https://gerrit.wikimedia.org/r/#/c/268196/
[x] 1.8 Discard changes to working directory and index on tin
[x] 1.9 Restore symlinks on deployment server - //pulled https://gerrit.wikimedia.org/r/#/c/268196/ on mira//
[ ] 1.10 Remove clones of expired branches - **skipped**
[ ] 1.11 Sync to cluster and verify on testwiki
[ ] 1.12 Remove left over files from expired branches
[ ] 1.13 Wait for deploy window
[ ] 1.14 Switch group0 wikis to VERSION
[ ] 1.15 Purge localization cache for now unused versions - //Probably fine now due to Tuesday staging wipe out//
[ ] 1.16 Update deploy notes
[ ] 1.17 Update roadmap