pgsql: doc: List all the possible values of pg_stat_wal_receiver.status

doc: List all the possible values of pg_stat_wal_receiver.status

The possible values of pg_stat_wal_receiver.status have never been
documented. Note that the status "stopped" will never show up in this
view, hence there is no need to document it.

Issue noticed while discussing a patch that aims to add a new status to
WAL receiver.

Author: Xuneng Zhou <xunengzhou@gmail.com>
Discussion: /messages/by-id/CABPTF7X_Jgmyk1FBVNf3tyAOKqU55LLpLMzWkGtEAb_jQWVN=g@mail.gmail.com

Branch
------
master

Details
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https://git.postgresql.org/pg/commitdiff/1a1e733b623108ebba8a6e6f55235782edb8f4bb

Modified Files
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doc/src/sgml/monitoring.sgml | 33 ++++++++++++++++++++++++++++++++-
1 file changed, 32 insertions(+), 1 deletion(-)