pgsql: doc: Improve consistency of parallel vacuum description.

doc: Improve consistency of parallel vacuum description.

Use consistent phrasing for parallel vacuum descriptions between
manual VACUUM and autovacuum. Specifically, clarify that the parallel
worker count is limited by the respective options only if they are
explicitly specified.

Also, fix a typo in the parallel vacuum section.

Author: Aleksander Alekseev <aleksander@tigerdata.com>
Discussion: https://postgr.es/m/CAJ7c6TPcSqzhbhrsiCMmVwmE8F7pwS7i9J49SP1zPKS_ER+vcA@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/2a3d2f9f68da0c430c497bf29f60373f5214307d

Modified Files
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doc/src/sgml/maintenance.sgml | 16 ++++++++--------
1 file changed, 8 insertions(+), 8 deletions(-)