pgsql: Fix DDL deparse of CREATE OPERATOR CLASS

Fix DDL deparse of CREATE OPERATOR CLASS

When an implicit operator family is created, it wasn't getting reported.
Make it do so.

This has always been missing.  Backpatch to 10.

Author: Masahiko Sawada <sawada.mshk@gmail.com>
Reported-by: Leslie LEMAIRE <leslie.lemaire@developpement-durable.gouv.fr>
Reviewed-by: Amit Kapila <amit.kapila16@gmail.com>
Reviewed-by: Michael Paquiër <michael@paquier.xyz>
Discussion: https://postgr.es/m/f74d69e151b22171e8829551b1159e77@developpement-durable.gouv.fr

Branch
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REL_11_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/6c6ea6ea81eb4385b109a59b93cdea0d91223aea

Modified Files
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src/backend/commands/opclasscmds.c                    | 19 ++++++++++++++-----
src/backend/tcop/utility.c                            |  6 ++++++
.../modules/test_ddl_deparse/expected/opfamily.out    |  1 +
src/test/regress/expected/event_trigger.out           |  5 +++++
src/test/regress/sql/event_trigger.sql                |  4 ++++
5 files changed, 30 insertions(+), 5 deletions(-)