Fabfile: || true commands

In what cases do the `|| true` commands bring any benefit? If a command fails, we should fail. This prevents us from seeing what the actual issue is. We should remove all `|| true` commands and handle the different scenarios correctly.

Inspect the Fabfile and locate every command using `|| true`; first determine which failures are being suppressed and what scenarios each command is intended to handle. Run the relevant test-automation commands while removing the suppression, and consider the work done when failures are visible and each affected scenario is handled explicitly.

Written by the indexing model from the issue text.