Documentation on how to sync Scribe-i18n subtrees

[Will Yoshida]

Terms

• I have searched open and closed issues
• I agree to follow Scribe-i18n's Code of Conduct

Issue

This issue is for adding a documentation guide detailing steps on how to sync the git subtrees in the Scribe application repos with the new changes in Scribe-i18n.

This can likely just be a section in the README.md