Add supported tables for group approval rules

What does this MR do?

This MR creates all tables required to support the management of group-level MR approval rules.

Since the DB changes are getting rather big, I will move the API to a separate MR to make reviewing a bit easier.

• High-level design #293957
• Implementation issue #325646 (closed)

🐘 Database

Migration/Rollback Log

Migrate

== 20210329124955 AddApprovalGroupRules: migrating ============================
-- create_table(:approval_group_rules, {:if_not_exists=>true})
   -> 0.0149s
-- transaction_open?()
   -> 0.0000s
-- current_schema()
   -> 0.0003s
-- execute("ALTER TABLE approval_group_rules\nADD CONSTRAINT check_25d42add43\nCHECK ( char_length(name) <= 255 )\nNOT VALID;\n")
   -> 0.0012s
-- current_schema()
   -> 0.0003s
-- execute("SET statement_timeout TO 0")
   -> 0.0010s
-- execute("ALTER TABLE approval_group_rules VALIDATE CONSTRAINT check_25d42add43;")
   -> 0.0014s
-- execute("RESET ALL")
   -> 0.0017s
== 20210329124955 AddApprovalGroupRules: migrated (0.0569s) ===================

== 20210330064326 AddApprovalGroupsRulesGroups: migrating =====================
-- create_table(:approval_group_rules_groups)
   -> 0.0070s
-- add_index(:approval_group_rules_groups, :approval_group_rule_id)
   -> 0.0054s
-- add_index(:approval_group_rules_groups, :group_id)
   -> 0.0045s
== 20210330064326 AddApprovalGroupsRulesGroups: migrated (0.0182s) ============

== 20210330064433 AddApprovalGroupsRulesUsers: migrating ======================
-- create_table(:approval_group_rules_users)
   -> 0.0077s
-- add_index(:approval_group_rules_users, :approval_group_rule_id)
   -> 0.0039s
-- add_index(:approval_group_rules_users, :user_id)
   -> 0.0049s
== 20210330064433 AddApprovalGroupsRulesUsers: migrated (0.0167s) =============

== 20210331051716 AddFkToApprovalRuleOnApprovalGroupRulesUsers: migrating =====
-- transaction_open?()
   -> 0.0000s
-- foreign_keys(:approval_group_rules_users)
   -> 0.0036s
-- execute("ALTER TABLE approval_group_rules_users\nADD CONSTRAINT fk_9a4b673183\nFOREIGN KEY (approval_group_rule_id)\nREFERENCES approval_group_rules (id)\nON DELETE CASCADE\nNOT VALID;\n")
   -> 0.0024s
-- execute("ALTER TABLE approval_group_rules_users VALIDATE CONSTRAINT fk_9a4b673183;")
   -> 0.0025s
== 20210331051716 AddFkToApprovalRuleOnApprovalGroupRulesUsers: migrated (0.0184s)

== 20210331051807 AddFkToUserOnApprovalGroupRulesUsers: migrating =============
-- transaction_open?()
   -> 0.0000s
-- foreign_keys(:approval_group_rules_users)
   -> 0.0022s
-- execute("ALTER TABLE approval_group_rules_users\nADD CONSTRAINT fk_888a0df3b7\nFOREIGN KEY (user_id)\nREFERENCES users (id)\nON DELETE CASCADE\nNOT VALID;\n")
   -> 0.0034s
-- execute("ALTER TABLE approval_group_rules_users VALIDATE CONSTRAINT fk_888a0df3b7;")
   -> 0.0033s
== 20210331051807 AddFkToUserOnApprovalGroupRulesUsers: migrated (0.0217s) ====

== 20210331051844 AddFkToApprovalRuleOnApprovalGroupRulesGroups: migrating ====
-- transaction_open?()
   -> 0.0000s
-- foreign_keys(:approval_group_rules_groups)
   -> 0.0022s
-- execute("ALTER TABLE approval_group_rules_groups\nADD CONSTRAINT fk_efff219a48\nFOREIGN KEY (approval_group_rule_id)\nREFERENCES approval_group_rules (id)\nON DELETE CASCADE\nNOT VALID;\n")
   -> 0.0023s
-- execute("ALTER TABLE approval_group_rules_groups VALIDATE CONSTRAINT fk_efff219a48;")
   -> 0.0016s
== 20210331051844 AddFkToApprovalRuleOnApprovalGroupRulesGroups: migrated (0.0179s)

== 20210331052026 AddFkToGroupOnApprovalGroupRulesGroups: migrating ===========
-- transaction_open?()
   -> 0.0000s
-- foreign_keys(:approval_group_rules_groups)
   -> 0.0030s
-- execute("ALTER TABLE approval_group_rules_groups\nADD CONSTRAINT fk_50edc8134e\nFOREIGN KEY (group_id)\nREFERENCES namespaces (id)\nON DELETE CASCADE\nNOT VALID;\n")
   -> 0.0024s
-- execute("ALTER TABLE approval_group_rules_groups VALIDATE CONSTRAINT fk_50edc8134e;")
   -> 0.0035s
== 20210331052026 AddFkToGroupOnApprovalGroupRulesGroups: migrated (0.0188s) ==

Rollback

== 20210331052026 AddFkToGroupOnApprovalGroupRulesGroups: reverting ===========
-- remove_foreign_key(:approval_group_rules_groups, {:column=>:group_id})
   -> 0.0040s
== 20210331052026 AddFkToGroupOnApprovalGroupRulesGroups: reverted (0.0101s) ==

== 20210331051844 AddFkToApprovalRuleOnApprovalGroupRulesGroups: reverting ====
-- remove_foreign_key(:approval_group_rules_groups, {:column=>:approval_group_rule_id})
   -> 0.0042s
== 20210331051844 AddFkToApprovalRuleOnApprovalGroupRulesGroups: reverted (0.0103s) 

== 20210331051807 AddFkToUserOnApprovalGroupRulesUsers: reverting =============
-- remove_foreign_key(:approval_group_rules_users, {:column=>:user_id})
   -> 0.0043s
== 20210331051807 AddFkToUserOnApprovalGroupRulesUsers: reverted (0.0107s) ====

== 20210331051716 AddFkToApprovalRuleOnApprovalGroupRulesUsers: reverting =====
-- remove_foreign_key(:approval_group_rules_users, {:column=>:approval_group_rule_id})
   -> 0.0043s
== 20210331051716 AddFkToApprovalRuleOnApprovalGroupRulesUsers: reverted (0.0106s) 

== 20210330064433 AddApprovalGroupsRulesUsers: reverting ======================
-- drop_table(:approval_group_rules_users)
   -> 0.0042s
== 20210330064433 AddApprovalGroupsRulesUsers: reverted (0.0044s) =============

== 20210330064326 AddApprovalGroupsRulesGroups: reverting =====================
-- drop_table(:approval_group_rules_groups)
   -> 0.0042s
== 20210330064326 AddApprovalGroupsRulesGroups: reverted (0.0043s) ============

== 20210329124955 AddApprovalGroupRules: reverting ============================
-- drop_table(:approval_group_rules)
   -> 0.0022s
== 20210329124955 AddApprovalGroupRules: reverted (0.0101s) ===================

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