Add creator_id to deploy_tokens

What does this MR do and why?

Describe in detail what your merge request does and why.

• Add a new column creator_id which will hold the id of the user who created the deploy token.
• While creating new deploy tokens (group or project) set the creator_id as the id of the current user.
• For old deploy tokens creator_id column would be NULL.
• When the creator is deleted set the creator_id as NULL.

Database

AddCreatorIdToDeployTokens up

https://console.postgres.ai/gitlab/gitlab-production-tunnel-pg12/sessions/9360/commands/33030

== 20220316095126 AddCreatorIdToDeployTokens: migrating =======================
-- add_column(:deploy_tokens, :creator_id, :bigint)
   -> 0.0018s
== 20220316095126 AddCreatorIdToDeployTokens: migrated (0.0018s) ==============

AddCreatorIdToDeployTokens down

== 20220316095126 AddCreatorIdToDeployTokens: reverting =======================
-- remove_column(:deploy_tokens, :creator_id, :bigint)
   -> 0.0018s
== 20220316095126 AddCreatorIdToDeployTokens: reverted (0.0019s) ==============

AddIndexToDeployTokensOnCreatorId up

https://console.postgres.ai/gitlab/gitlab-production-tunnel-pg12/sessions/9331/commands/32920

== 20220316102900 AddIndexToDeployTokensOnCreatorId: migrating ================
-- transaction_open?()
   -> 0.0000s
-- index_exists?(:deploy_tokens, :creator_id, {:name=>"index_deploy_tokens_on_creator_id", :algorithm=>:concurrently})
   -> 0.0046s
-- execute("SET statement_timeout TO 0")
   -> 0.0007s
-- add_index(:deploy_tokens, :creator_id, {:name=>"index_deploy_tokens_on_creator_id", :algorithm=>:concurrently})
   -> 0.0029s
-- execute("RESET statement_timeout")
   -> 0.0006s
== 20220316102900 AddIndexToDeployTokensOnCreatorId: migrated (0.0177s) =======

AddIndexToDeployTokensOnCreatorId down

== 20220316102900 AddIndexToDeployTokensOnCreatorId: reverting ================
-- transaction_open?()
   -> 0.0000s
-- index_exists?(:deploy_tokens, :creator_id, {:name=>"index_deploy_tokens_on_creator_id", :algorithm=>:concurrently})
   -> 0.0023s
-- remove_index(:deploy_tokens, {:name=>"index_deploy_tokens_on_creator_id", :algorithm=>:concurrently, :column=>:creator_id})
   -> 0.0038s
== 20220316102900 AddIndexToDeployTokensOnCreatorId: reverted (0.0084s) =======

AddUserForeignKeyToDeployTokens up

https://console.postgres.ai/gitlab/gitlab-production-tunnel-pg12/sessions/9263/commands/32759

== 20220316102902 AddUserForeignKeyToDeployTokens: migrating ==================
-- transaction_open?()
   -> 0.0000s
-- foreign_keys(:deploy_tokens)
   -> 0.0037s
-- transaction_open?()
   -> 0.0000s
-- execute("LOCK TABLE users, deploy_tokens IN SHARE ROW EXCLUSIVE MODE")
   -> 0.0007s
-- execute("ALTER TABLE deploy_tokens\nADD CONSTRAINT fk_7082f8a288\nFOREIGN KEY (creator_id)\nREFERENCES users (id)\nON DELETE SET NULL\nNOT VALID;\n")
   -> 0.0022s
-- execute("ALTER TABLE deploy_tokens VALIDATE CONSTRAINT fk_7082f8a288;")
   -> 0.0045s
== 20220316102902 AddUserForeignKeyToDeployTokens: migrated (0.0208s) =========

AddUserForeignKeyToDeployTokens down

== 20220316102902 AddUserForeignKeyToDeployTokens: reverting ==================
-- transaction_open?()
   -> 0.0000s
-- remove_foreign_key(:deploy_tokens, {:column=>:creator_id})
   -> 0.0040s
== 20220316102902 AddUserForeignKeyToDeployTokens: reverted (0.0073s) =========

Screenshots or screen recordings

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How to set up and validate locally

Numbered steps to set up and validate the change are strongly suggested.

1. You must have ultimate license.
2. Create a group or a project deploy token following the steps in the doc.
3. Verify from the Rails console that the deploy token that is created has creator_id set to the user who created the user. DeployToken.last.creator_id.
4. Verify that creator is returned DeployToken.last.user.

Relates to #https://gitlab.com/gitlab-org/gitlab/-/issues/353467

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.