pgsql: Don't force materializing when copying a buffer tuple tableslot

Don't force materializing when copying a buffer tuple table slot.

After 5408e233f0667478 it's not necessary to force materializing the
target slot when copying from one buffer slot to another. Previously
that was required because the HeapTupleData portion of the source slot
wasn't guaranteed to stay valid long enough, but now we can simply
copy that part into the destination slot's tupdata.

Author: Andres Freund

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/8f0577386e68c3b1c83a07b95756e5ee3f4ae73f

Modified Files
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src/backend/executor/execTuples.c | 19 +++++++++++--------
1 file changed, 11 insertions(+), 8 deletions(-)