pgsql: Improve tab completion of CREATE EVENT TRIGGER in psql

Improve tab completion of CREATE EVENT TRIGGER in psql

This adds tab completion of the clauses WHEN and EXECUTE
FUNCTION|PROCEDURE clauses to CREATE EVENT TRIGGER, similar to CREATE
TRIGGER in the previous commit.  This has version-dependent logic so as
FUNCTION is chosen over PROCEDURE for 11 and newer versions.

Author: Dagfinn Ilmari Mannsåker
Reviewed-by: Tom Lane, Michael Paquier
Discussion: https://postgr.es/m/d8jmur4q4yc.fsf@dalvik.ping.uio.no

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/5953c99697621174f50aa219a3cd457212968268

Modified Files
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src/bin/psql/tab-complete.c | 23 +++++++++++++++++++++++
1 file changed, 23 insertions(+)