Обсуждение: pgsql: Fix the errhint message and docs for drop subscription failure.

Fix the errhint message and docs for drop subscription failure.

The existing errhint message and docs were missing the fact that we can't
disassociate from the slot unless the subscription is disabled.

Author: Robert Sjöblom, Peter Smith
Reviewed-by: Peter Eisentraut, Amit Kapila
Backpatch-through: 11
Discussion: https://postgr.es/m/807bdf85-61ea-88e2-5712-6d9fcd4eabff@fortnox.se

Branch
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REL_12_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/0e73b9ae6c5f661fbe5c14332351190588741e52

Modified Files
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doc/src/sgml/ref/drop_subscription.sgml | 8 +++++---
src/backend/commands/subscriptioncmds.c | 3 ++-
2 files changed, 7 insertions(+), 4 deletions(-)