pgsql: In SPGiST replay, do conflict resolution before modifying the pa

In SPGiST replay, do conflict resolution before modifying the page.

In yesterday's commit 962e0cc71e839c58fb9125fa85511b8bbb8bdbee, I added the
ResolveRecoveryConflictWithSnapshot call in the wrong place.  I correctly
put it before spgRedoVacuumRedirect itself would modify the index page ---
but not before RestoreBkpBlocks, so replay of a record with a full-page
image would modify the page before kicking off any conflicting HS
transactions.  Oops.

Branch
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master

Details
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http://git.postgresql.org/pg/commitdiff/c1793f2e0ce4ee5c713f27d0bdacc7d99b9103ac

Modified Files
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src/backend/access/spgist/spgxlog.c |   40 +++++++++++++++++++++++-----------
1 files changed, 27 insertions(+), 13 deletions(-)