pgsql: Doc: reword text explaining the --maintenance-db option - Mailing list pgsql-committers

Doc: reword text explaining the --maintenance-db option

The previous text was a little clumsy.  Here we improve that.

Author: David Rowley <dgrowleyml@gmail.com>
Reported-by: Noboru Saito <noborusai@gmail.com>
Reviewed-by: David G. Johnston <david.g.johnston@gmail.com>
Discussion: https://postgr.es/m/CAAM3qnJtv5YbjpwDfVOYN2gZ9zGSLFM1UGJgptSXmwfifOZJFQ@mail.gmail.com
Backpatch-through: 13

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/9a5da12aba42dbb75efd876ca245e54cebd64ec2

Modified Files
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doc/src/sgml/ref/clusterdb.sgml | 5 ++---
doc/src/sgml/ref/reindexdb.sgml | 5 ++---
doc/src/sgml/ref/vacuumdb.sgml  | 5 ++---
3 files changed, 6 insertions(+), 9 deletions(-)