Обсуждение: pgsql: docs: add xreflabel entries for autovacuum, SP-GiST, and TOAST

docs:  add xreflabel entries for autovacuum, SP-GiST, and TOAST

This is for use by the PG 13 release notes, but might be used for minor
release notes in the future.

Backpatch-through: 9.5

Branch
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REL9_5_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/87ca0f94d6ea27cc8db83cab8e7bb652ef383168

Modified Files
--------------
doc/src/sgml/maintenance.sgml | 2 +-
doc/src/sgml/spgist.sgml      | 2 +-
doc/src/sgml/storage.sgml     | 2 +-
3 files changed, 3 insertions(+), 3 deletions(-)