Add note about git add for rsync tracking

[jeryj]

Proposed changes:

• Add note about needing to git add files before rsync will track it.

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[jeherve]

Thanks for adding this in!

I was a bit confused by that monorepo link in the preview:

Do you think you could take that opportunity to remove it, and move the link here instead?

jetpack/tools/cli/README.md

Line 3 in 7f07bc7

The `jetpack` CLI tool is used to help with development in [the Jetpack monorepo].

[kraftbj]

Related: #41442

[jeryj]

@jeherve - I was wondering about that one. Nice catch! I moved the link to where it was intended.