Fixes docs ref to SSH over Tor settings
Fixes docs ref to SSH over Tor settings

The addition of the `pip_update.sh` script to the developer docs broke
the Sphinx `ref` to SSH over Tor settings. This was missed during review
of #1674. A simple fix: simply move the ref declaration below the
pip_update.sh block, so it again correctly points to the SSH over Tor
docs.

ageis/securedrop,ageis/securedrop,garrettr/securedrop,garrettr/securedrop,garrettr/securedrop,conorsch/securedrop,micahflee/securedrop,conorsch/securedrop,heartsucker/securedrop,ehartsuyker/securedrop,heartsucker/securedrop,heartsucker/securedrop,ehartsuyker/securedrop,ageis/securedrop,ehartsuyker/securedrop,ehartsuyker/securedrop,ehartsuyker/securedrop,ageis/securedrop,micahflee/securedrop,garrettr/securedrop,micahflee/securedrop,heartsucker/securedrop,ehartsuyker/securedrop,conorsch/securedrop,conorsch/securedrop,micahflee/securedrop,heartsucker/securedrop,conorsch/securedrop