Update Largo submodule to tagged v0.6.3

[benlk]

When that is released:

This requires testing on all inn.org domains and subdomains.

• [ ] impaq.inn.org
• [ ] inn.org (create separate issue in github.com/inn/inn for issues with this domain)
• [ ] innovation.inn.org
• [x] ~labs.inn.org (is this on Largo?)~
• [ ] largo.inn.org
• [x] largoproject.org redirects to largo.inn.org
• [ ] learn.inn.org
• [x] nerds.inn.org redirects to labs.inn.org
• other redirects not listed here, don't need to be checked

[benlk]

Updated to 0.6.3 for https://github.com/INN/umbrella-inndev/issues/59

[benlk]

When doing this, update the Largo version on largo.inn.org: https://github.com/INN/umbrella-inndev/commit/4d206f1d438a6c6bb685c68005c76c795c6df741