pgsql: Stabilize pg_dump output order for similarly-named triggers and

Stabilize pg_dump output order for similarly-named triggers and policies.

The code only compared two triggers' names and namespaces (the latter
being the owning table's schema). This could result in falling back
to an OID-based sort of similarly-named triggers on different tables.
We prefer to avoid that, so add a comparison of the table names too.
(The sort order is thus table namespace, trigger name, table name,
which is a bit odd, but it doesn't seem worth contorting the code
to work around that.)

Likewise for policy objects, in 9.5 and up.

Complaint and fix by Benjie Gillam. Back-patch to all supported
branches.

Discussion: https://postgr.es/m/CAMThMzEEt2mvBbPgCaZ1Ap1N-moGn=Edxmadddjq89WG4NpPtQ@mail.gmail.com

Branch
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REL9_6_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/648f17879e61e9faa007eab56331afe77b696c1e

Modified Files
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src/bin/pg_dump/pg_dump_sort.c | 24 ++++++++++++++++++++++++
1 file changed, 24 insertions(+)