pgsql: Fix RELCACHE_FORCE_RELEASE issue

Fix RELCACHE_FORCE_RELEASE issue

Introduced by 83fd4532a72179c370e318075a10e0e2aa832024.  To fix, the
tuple descriptors need to be copied into the current memory context.

Discussion: https://www.postgresql.org/message-id/04d78603-edae-9243-9dde-fe3037176a7d@2ndquadrant.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/12fb189bfeaf03faea5b6f15544c1f71e9ef4677

Modified Files
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src/backend/replication/pgoutput/pgoutput.c | 3 ++-
1 file changed, 2 insertions(+), 1 deletion(-)