Make sure nova-compute is not configured with database access

Apparently we're inheriting some database config from the main file,
which should not be set for nova-compute. If we're properly in superconductor
mode where we have a dedicated config for compute, remove those lines
if present.

Closes-Bug: #1797413

Change-Id: I4820abe57a023050dd8d067c77e26028801ff288
1 file changed