pgsql: ATTACH PARTITION: Don't match a PK with a UNIQUE constraint

ATTACH PARTITION: Don't match a PK with a UNIQUE constraint

When matching constraints in AttachPartitionEnsureIndexes() we weren't
testing the constraint type, which could make a UNIQUE key lacking a
not-null constraint incorrectly satisfy a primary key requirement.  Fix
this by testing that the constraint types match.  (Other possible
mismatches are verified by comparing index properties.)

Discussion: https://postgr.es/m/202402051447.wimb4xmtiiyb@alvherre.pgsql

Branch
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master

Details
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https://git.postgresql.org/pg/commitdiff/cee8db3f680b737b64d747530b48d30828cf4790

Modified Files
--------------
src/backend/commands/tablecmds.c          |  5 +++++
src/backend/utils/cache/lsyscache.c       | 22 ++++++++++++++++++++++
src/include/utils/lsyscache.h             |  2 ++
src/test/regress/expected/constraints.out | 16 ++++++++++++++++
src/test/regress/sql/constraints.sql      |  7 +++++++
5 files changed, 52 insertions(+)