pgsql: Revert test added by commit d207038053.

Revert test added by commit d207038053.

This test was trying to test the mechanism to release kernel FDs as needed
to get us under the max_safe_fds limit in case of spill files.  To do that,
it needs to set max_files_per_process to a very low value which doesn't
even permit starting of the server in the case when there are a few already
opened files.  This test also won't work on platforms where we use one FD
per semaphore.

Backpatch-through: 10, till where this test was added
Discussion:
https://postgr.es/m/CAA4eK1LHhERi06Q+MmP9qBXBBboi+7WV3910J0aUgz71LcnKAw@mail.gmail.com
https://postgr.es/m/6485.1578583522@sss.pgh.pa.us

Branch
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REL_10_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/f9e95252a311b65e3e5aa9cb56cec2736e2b1cfa

Modified Files
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src/test/recovery/t/006_logical_decoding.pl | 39 +----------------------------
1 file changed, 1 insertion(+), 38 deletions(-)