pgsql: Create regress_tblspc in test_setup

Create regress_tblspc in test_setup

An upcoming test needs to use a tablespace as part of its test. Historically,
we wanted tablespace creation be done in a dedicated file, so it's easy to
disable when testing replication. But that is not necessary anymore, due to
allow_in_place_tablespaces.

Create regress_tblspace tablespace in test_setup. Move the tablespace test to
the end of the parallel schedule, so other tests can use it.

Author: Melanie Plageman <melanieplageman(at)gmail(dot)com>
Reviewed-by: Andres Freund <andres(at)anarazel(dot)de>
Discussion: https://postgr.es/m/20200124195226.lth52iydq2n2uilq@alap3.anarazel.de

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/9c83bbcf7ef6b4236d117b25d8a754483e6488db

Modified Files
--------------
src/test/regress/expected/tablespace.out | 4 +---
src/test/regress/expected/test_setup.out | 3 +++
src/test/regress/parallel_schedule | 9 ++++-----
src/test/regress/sql/tablespace.sql | 4 +---
src/test/regress/sql/test_setup.sql | 4 ++++
5 files changed, 13 insertions(+), 11 deletions(-)