pgsql: Add new simple TAP test for tablespaces.

Add new simple TAP test for tablespaces.

The tablespace tests in the main regression tests have been changed to
use "in-place" tablespaces, so that they work when streamed to a replica
on the same host. Add a new TAP test that exercises tablespaces with
absolute paths, for coverage.

Reviewed-by: Andres Freund <andres(at)anarazel(dot)de>
Reviewed-by: Michael Paquier <michael(at)paquier(dot)xyz>
Discussion: https://postgr.es/m/CA%2BhUKGKpRWQ9SxdxxDmTBCJoR0YnFpMBe7kyzY8SUQk%2BHeskxg%40mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/d1511fe1b040853f6e10d353e56b42bb96ae239d

Modified Files
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src/test/modules/test_misc/t/002_tablespace.pl | 96 ++++++++++++++++++++++++++
1 file changed, 96 insertions(+)