Due to the changes of the default view behaviour of continuous
aggregates we need a new testsuite for the update tests for 1.7.0
This patch also changes the update test for 9.6 and 10 to run on
cron and 11 and 12 on pull request.
PG11 added an optimization where columns that were added by
an ALTER TABLE that had a DEFAULT value did not cause a table
re-write. Instead, those columns are filled with the default
value on read.
But, this mechanism does not apply to catalog tables and does
not work with our catalog scanning code. This tests makes
sure we never have such alters in our updates.