Duplicate check constraints being generated in schema:dump with multiple db schemas

[frank-west-iii]

Steps to reproduce

I've create a repo with more information and reproduction steps here: https://github.com/frank-west-iii/check_demo

Additional tracing info:

rails/activerecord/lib/active_record/connection_adapters/postgresql/schema_statements.rb

Line 535 in a9bbc92

check_info.map do |row|

check_info
[
  {"conname"=>"users_email_null", "constraintdef"=>"CHECK (email IS NOT NULL) NOT VALID", "valid"=>false},
  {"conname"=>"users_email_null", "constraintdef"=>"CHECK (email IS NOT NULL) NOT VALID", "valid"=>false}
]

Updating to use DISTINCT "fixes" the issue, but that is very likely not the right fix for this issue and is now approaching my edge of knowledge.

          check_info = exec_query(<<-SQL, "SCHEMA")
            SELECT DISTINCT conname, pg_get_constraintdef(c.oid, true) AS constraintdef, c.convalidated AS valid
            FROM pg_constraint c
            JOIN pg_class t ON c.conrelid = t.oid
            WHERE c.contype = 'c'
              AND t.relname = #{scope[:name]}
          SQL

Expected behavior

Dumping the db schema should not duplicate check constraints when multiple schemas are present in the database

ApplicationRecord.connection.check_constraints("users")
=> [#<struct ActiveRecord::ConnectionAdapters::CheckConstraintDefinition table_name="users", expression="email IS NOT NULL", options={:name=>"users_email_null", :validate=>false}>]

Actual behavior

Dumping the db schema creates a duplicate check constraints entry when multiple schemas are present in the database

ApplicationRecord.connection.check_constraints("users")
=> [#<struct ActiveRecord::ConnectionAdapters::CheckConstraintDefinition table_name="users", expression="email IS NOT NULL", options={:name=>"users_email_null", :validate=>false}>, #<struct ActiveRecord::ConnectionAdapters::CheckConstraintDefinition table_name="users", expression="email IS NOT NULL", options={:name=>"users_email_null", :validate=>false}>]

System configuration

Rails version: 7.0.2.3

Ruby version: 3.1.1p18