pgsql: Login event trigger documentation wordsmithing

Login event trigger documentation wordsmithing

Minor wordsmithing on the login trigger documentation and code
comments to improve readability, as well as fixing a few small
incorrect statements in the comments.

Author: Robert Treat <rob@xzilla.net>
Discussion: /messages/by-id/CAJSLCQ0aMWUh1m6E9YdjeqV61baQ=EhteJX8XOxXg8H_2Lcr0Q@mail.gmail.com

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/4665cebc8a01dabd54b000bcc107a3468be3a81c

Modified Files
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doc/src/sgml/event-trigger.sgml | 10 +++++-----
src/backend/commands/event_trigger.c | 18 +++++++++---------
2 files changed, 14 insertions(+), 14 deletions(-)