Обсуждение: pgsql: Fix dependency on FDW handler.

Fix dependency on FDW handler.

ALTER FOREIGN DATA WRAPPER could drop the dependency on the handler
function if it wasn't explicitly specified.

Reviewed-by: Nathan Bossart <nathandbossart@gmail.com>
Discussion: https://postgr.es/m/35c44a4b7fb76d35418c4d66b775a88f4ce60c86.camel@j-davis.com
Backpatch-through: 14

Branch
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REL_15_STABLE

Details
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https://git.postgresql.org/pg/commitdiff/3a35ab1d0126802045e7133788647a549ea6fa98

Modified Files
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src/backend/commands/foreigncmds.c         | 5 +++++
src/test/regress/expected/foreign_data.out | 7 +++++++
src/test/regress/sql/foreign_data.sql      | 5 +++++
3 files changed, 17 insertions(+)