Revert "Merge branch '202423-validate-foreign-key-on-group-hooks' into 'master'"

This reverts merge request !60266

changelogs/unreleased/202423-validate-foreign-key-on-group-hooks.yml

----
-title: Validate foreign key on GroupHooks
-merge_request: 60266
-author:
-type: other

db/migrate/20210426091650_validate_foreign_key_on_group_hooks.rb

-# frozen_string_literal: true
-
-class ValidateForeignKeyOnGroupHooks < ActiveRecord::Migration[6.0]
-  include Gitlab::Database::MigrationHelpers
-
-  CONSTRAINT_NAME = 'fk_rails_d35697648e'
-
-  def up
-    validate_foreign_key :web_hooks, :group_id, name: CONSTRAINT_NAME
-  end
-
-  def down
-    # no-op
-  end
-end

db/schema_migrations/20210426091650

-e7020e969ea589d4de50bdae7c8c43f52acb1c886d4f9203ff45f631e057d7bc
\ No newline at end of file

db/structure.sql

@@ -26727,7 +26727,7 @@ ALTER TABLE ONLY pool_repositories
     ADD CONSTRAINT fk_rails_d2711daad4 FOREIGN KEY (source_project_id) REFERENCES projects(id) ON DELETE SET NULL;
 
 ALTER TABLE ONLY web_hooks
-    ADD CONSTRAINT fk_rails_d35697648e FOREIGN KEY (group_id) REFERENCES namespaces(id) ON DELETE CASCADE;
+    ADD CONSTRAINT fk_rails_d35697648e FOREIGN KEY (group_id) REFERENCES namespaces(id) ON DELETE CASCADE NOT VALID;
 
 ALTER TABLE ONLY group_group_links
     ADD CONSTRAINT fk_rails_d3a0488427 FOREIGN KEY (shared_group_id) REFERENCES namespaces(id) ON DELETE CASCADE;

ee/app/models/ee/group.rb

@@ -30,7 +30,7 @@ module EE
 
       has_many :ldap_group_links, foreign_key: 'group_id', dependent: :destroy # rubocop:disable Cop/ActiveRecordDependent
       has_many :saml_group_links, foreign_key: 'group_id'
-      has_many :hooks, class_name: 'GroupHook'
+      has_many :hooks, dependent: :destroy, class_name: 'GroupHook' # rubocop:disable Cop/ActiveRecordDependent
 
       has_many :allowed_email_domains, -> { order(id: :asc) }, autosave: true