pgsql: Reduce comments

Reduce comments

Reduce the vertical space used by comments in ri_triggers.c, making
the file longer and more tedious to read than it needs to be.  Update
some comments to use a more common style.

Reviewed-by: Corey Huinker <corey.huinker@gmail.com>
Discussion: https://www.postgresql.org/message-id/flat/0ccdd3e1-10b0-dd05-d8a7-183507c11eb1%402ndquadrant.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/05d604718f7fec7db33548374ecde3f11916ec15

Modified Files
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src/backend/utils/adt/ri_triggers.c | 379 +++++++++++++-----------------------
1 file changed, 133 insertions(+), 246 deletions(-)