Adds ./ to manage.py invocations in admin docs
Adds ./ to manage.py invocations in admin docs

Same as we do elsewhere, in codeblocks, let's explicitly prefix the
"manage.py" executable with "./", since Admins will need to type that
invocation exactly in order for the subcommand to work.

conorsch/securedrop,conorsch/securedrop,conorsch/securedrop,conorsch/securedrop,conorsch/securedrop