pgsql: docs: make monitoring "phases" table titles consistent

docs:  make monitoring "phases" table titles consistent

Reported-by: Nitin Jadhav

Discussion: https://postgr.es/m/CAMm1aWbmTHwHKC2PERH0CCaFVPoxrtLeS8=wNuoge94qdSp3vA@mail.gmail.com

Author: Nitin Jadhav

Backpatch-through: 13

Branch
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REL_14_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/e1d5ac3118be2c8f93a7b9c8813027f7a7f8d049

Modified Files
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doc/src/sgml/monitoring.sgml | 4 ++--
1 file changed, 2 insertions(+), 2 deletions(-)