Announcement: Try push via Lando

[Connor Sheehan]

Hello Firefox devs,

Tl;dr: You can now use a --push-to-lando flag with mach try, which will greatly reduce the submission time on your try pushes.

Earlier today I landed a patch that adds a new --push-to-lando flag to mach try. When this flag is used, mach try will gather patch files for each revision in your commit stack and submit them to Lando for queueing on try, instead of submitting to try directly. Using this flag significantly reduces the try push time, to about 10-20 seconds. Authentication in this workflow is handled via Mozilla SSO instead of SSH keys.

Please give the new push mechanism a try. If you have feedback or problems with the new workflow, please come to #lando-try-push on Slack or #conduit on chat.mozilla.org. Bugs can be filed in the Conduit :: Lando or `Developer Infrastructure :: Try` components on Bugzilla. Please mark them as blocking https://bugzilla.mozilla.org/show_bug.cgi?id=lando-try-push. 

This will become the default option in the near future.

Cheers,

Connor