pgsql: Fix 007_sync_rep.pl to notice failures in ALTER SYSTEM SET.

Fix 007_sync_rep.pl to notice failures in ALTER SYSTEM SET.

If a test case tried to set an invalid value of synchronous_standby_names,
the test script didn't detect that, which seems like a bad idea.
Noticed while testing a proposed patch that broke some of these
test cases.

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/fb57f40eec503d637bf01c298f5cb2472f0d4fdb

Modified Files
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src/test/recovery/t/007_sync_rep.pl | 2 +-
1 file changed, 1 insertion(+), 1 deletion(-)