Update "Support Request" template in line with Gitaly's intake workflow.
I'd like to link directly to this from https://about.gitlab.com/handbook/engineering/development/dev/gitaly/#how-to-contact-the-team, so that labels are set automatically.
Cc'ing team EM on new customer issues. Adding labels in accordance with https://about.gitlab.com/handbook/product-development-flow/#workflow-summary hopefully.