pgsql: For 11 only, put back heap_expand_tuple to GetTupleForTrigger().

For 11 only, put back heap_expand_tuple to GetTupleForTrigger().

This is not necessary anymore after 297d627e, but extensions that have
not been recompiled after the fix will not use the new definition of
heap_getattr(). While recompiling those extensions is obviously the
suggested course, it's cheap enough to retain the expansion in
GetTupleForTrigger().

Per suggestion from Andrew Gierth.

Discussion: 87va1x43ot(dot)fsf(at)news-spur(dot)riddles(dot)org(dot)uk

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/920311ab18aac799aee6ad2303b2ed2b6b44c1b8

Modified Files
--------------
src/backend/commands/trigger.c | 10 +++++++++-
1 file changed, 9 insertions(+), 1 deletion(-)