This issue is part of #2157455: [Meta] Make Drupal 8 work with PostgreSQL.
Currently there is one or more fail or exception in the views test group identified by the new docker based testbot that need to be fixed to make PostgreSQL finally passing all tests. Command in use:
sudo DCI_DBTYPE='pgsql' \
DCI_DBVER='9.1' \
DCI_PHPVERSION='5.5' \
DCI_CONCURRENCY='4' \
DCI_TESTGROUPS='views' \
DCI_DRUPALBRANCH='8.0.x' \
DCI_VERBOSE='true' \
DCI_UPDATEREPO='true' \
./containers/web/run.sh