Add filter for spurious PG warnings/errors
Add filter for spurious PG warnings/errors

- A number of warnings in pg_restore cannot be avoided during transition
to RDS.

- The errors will disappear after migration

@schmie

alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet,alphagov/govuk-puppet