pgsql: doc PG 17 relnotes: move EXPLAIN items to their own section

doc PG 17 relnotes: move EXPLAIN items to their own section

Reported-by: Álvaro Herrera

Discussion: /messages/by-id/202409111750.xtcbl7ppdoyn@alvherre.pgsql

Backpatch-through: 17 only

Branch
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REL_17_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/984702d0ee9b196dd0a68d4202a42f0bb14562dd

Modified Files
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doc/src/sgml/release-17.sgml | 151 +++++++++++++++++++++++--------------------
1 file changed, 80 insertions(+), 71 deletions(-)