Ensure all passwords are quoted in ERB template content

Summary

Related to #1207 (closed)

To ensure there is no formatting problems, we should be ensuring at all passwords are quoted or escaped during their output in ERB templates.

  1. charts/gitlab/templates/_smtp.tpl
  2. charts/gitlab/templates/_redis.tpl

To be kept in mind: if we're wrapping passwords in ", we have to escape them in the event that a password actually contains ". (for reference https://gitlab.com/charts/gitlab/merge_requests/717/diffs)

A customer has reported that the actually ended up with a failure because we started quoting the password for their database, but did not take escape sequences into account.

Edited by Jason Plum