Drop ignored column requirement_id

Related to #345845 (closed)

What does this MR do and why?

The column requirements_management_test_reports.requirement_id was ignored in !82134 (merged) and it's ready to be removed from the table.

The ignore rule is scheduled to be removed in %15.1 with #361225 (closed).

Migration

bin/rails db:migrate:up VERSION=20220503134610

== 20220503134610 RemoveRequirementsManagementTestReportsRequirementId: migrating 
-- transaction_open?()
   -> 0.0000s
-- remove_column(:requirements_management_test_reports, :requirement_id)
   -> 0.0035s
== 20220503134610 RemoveRequirementsManagementTestReportsRequirementId: migrated (0.0241s)

bin/rails db:migrate:down VERSION=20220503134610

== 20220503134610 RemoveRequirementsManagementTestReportsRequirementId: reverting 
-- column_exists?(:requirements_management_test_reports, :requirement_id)
   -> 0.0082s
-- add_column(:requirements_management_test_reports, :requirement_id, :bigint, {:after=>:created_at})
   -> 0.0025s
-- transaction_open?()
   -> 0.0000s
-- index_exists?(:requirements_management_test_reports, :requirement_id, {:name=>:index_requirements_management_test_reports_on_requirement_id, :algorithm=>:concurrently})
   -> 0.0052s
-- execute("SET statement_timeout TO 0")
   -> 0.0008s
-- add_index(:requirements_management_test_reports, :requirement_id, {:name=>:index_requirements_management_test_reports_on_requirement_id, :algorithm=>:concurrently})
   -> 0.0049s
-- execute("RESET statement_timeout")
   -> 0.0010s
-- transaction_open?()
   -> 0.0000s
-- foreign_keys(:requirements_management_test_reports)
   -> 0.0052s
-- transaction_open?()
   -> 0.0000s
-- execute("ALTER TABLE requirements_management_test_reports\nADD CONSTRAINT fk_rails_fb3308ad55\nFOREIGN KEY (requirement_id)\nREFERENCES requirements (id)\nON DELETE CASCADE\nNOT VALID;\n")
   -> 0.0024s
-- execute("ALTER TABLE requirements_management_test_reports VALIDATE CONSTRAINT fk_rails_fb3308ad55;")
   -> 0.0034s
== 20220503134610 RemoveRequirementsManagementTestReportsRequirementId: reverted (0.0606s) 

MR acceptance checklist

This checklist encourages us to confirm any changes have been analyzed to reduce risks in quality, performance, reliability, security, and maintainability.

• I have evaluated the MR acceptance checklist for this MR.

db/post_migrate/20220503134610_remove_requirements_management_test_reports_requirement_id.rb

+# frozen_string_literal: true
+
+class RemoveRequirementsManagementTestReportsRequirementId < Gitlab::Database::Migration[2.0]
+  disable_ddl_transaction!
+
+  TARGET_TABLE = :requirements_management_test_reports
+  CONSTRAINT_NAME = 'fk_rails_fb3308ad55'
+
+  def up
+    with_lock_retries do
+      remove_column TARGET_TABLE, :requirement_id
+    end
+  end
+
+  def down
+    unless column_exists?(TARGET_TABLE, :requirement_id)
+      with_lock_retries do
+        add_column TARGET_TABLE, :requirement_id, :bigint, after: :created_at
+      end
+    end
+
+    add_concurrent_index TARGET_TABLE, :requirement_id,
+      name: :index_requirements_management_test_reports_on_requirement_id
+
+    add_concurrent_foreign_key TARGET_TABLE, :requirements,
+      column: :requirement_id, name: CONSTRAINT_NAME, on_delete: :cascade
+  end
+end