pgsql: doc: Get rid of unnecessary space character from some index item

doc: Get rid of unnecessary space character from some index items.

Previously some index items have " ," (i.e., space + comma) in the docs
as follows. Since the space character before the comma is unnecessary,
this commit gets rid of that for the sake of consistency with other
index items.

   parallel_leader_participation configuration parameter , Other Planner Options

Author: Fujii Masao
Reviewed-by: Euler Taveira
Discussion: https://postgr.es/m/e87b4ddf-1498-2850-bf55-519df3928fd4@oss.nttdata.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/e522024bd8dd28a0f13dcccfd39170698f45c939

Modified Files
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doc/src/sgml/config.sgml | 5 +----
doc/src/sgml/pgtrgm.sgml | 8 ++------
2 files changed, 3 insertions(+), 10 deletions(-)