pgsql: Don't malloc(0) in EventTriggerCollectAlterTSConfig

Don't malloc(0) in EventTriggerCollectAlterTSConfig

Author: Florin Irion <florin.irion@enterprisedb.com>
Discussion: https://postgr.es/m/c6fff161-9aee-4290-9ada-71e21e4d84de@gmail.com

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/988b9588dadbcc3f53bd4ba853a43c9208d450f2

Modified Files
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src/backend/commands/event_trigger.c                      | 7 +++++--
src/test/modules/test_ddl_deparse/Makefile                | 1 +
src/test/modules/test_ddl_deparse/expected/textsearch.out | 5 +++++
src/test/modules/test_ddl_deparse/sql/textsearch.sql      | 3 +++
4 files changed, 14 insertions(+), 2 deletions(-)