pgsql: Re-order some regression test scripts for more parallelism.

Re-order some regression test scripts for more parallelism.

Move the strings, numerology, insert, insert_conflict, select and
errors tests to be parts of nearby parallel groups, instead of
executing by themselves.  (Moving "select" required adjusting the
constraints test, which uses a table named "tmp" as select also
does.  There don't seem to be any other conflicts.)

Move psql and stats_ext to the next parallel group, where the rules
test also has a long runtime.  To make it safe to run stats_ext in
parallel with rules, I adjusted the latter to only dump views/rules
from the pg_catalog and public schemas, which was what it was doing
anyway.  stats_ext makes some views in a transient schema, which now
will not affect rules.

Reorder serial_schedule to match parallel_schedule.

Discussion: https://postgr.es/m/735.1554935715@sss.pgh.pa.us

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/798070ec058fe75757587c9e9916cc35c623f427

Modified Files
--------------
src/test/regress/expected/rules.out        |  7 ++++--
src/test/regress/expected/sanity_check.out |  1 +
src/test/regress/input/constraints.source  |  2 +-
src/test/regress/output/constraints.source |  2 +-
src/test/regress/parallel_schedule         | 36 +++++++++++-------------------
src/test/regress/serial_schedule           | 20 ++++++++---------
src/test/regress/sql/rules.sql             |  7 ++++--
7 files changed, 36 insertions(+), 39 deletions(-)