Add `deploy_key_id` field to `protected_tag_create_access_levels`

What does this MR do and why?

Contributes to #325415 (closed)

Roadmap

Step	MR
Database migration to add deploy_key_id	👈 this MR
Add associations and validations	!109911 (merged)
Enable verification for protected tags creation	!110238 (merged)
Allow users to choose Deploy keys for protected tags	!110047 (merged)
Documentation	!110240 (merged)

Problem

We support deploy keys only for protected branches, but this functionality is missing for protected tags.

Solution

This commit adds a new field deploy_key_id to match the same field in protected_branches_push_access_levels table.

Database

Up

main: == 20230124122143 AddDeployKeyIdToCreateAccessLevels: migrating ===============
main: -- add_column(:protected_tag_create_access_levels, :deploy_key_id, :integer)
main:    -> 0.0027s
main: == 20230124122143 AddDeployKeyIdToCreateAccessLevels: migrated (0.0039s) ======

main: == 20230124193917 AddIndexForProtectedTagCreateAccessLevels: migrating ========
main: -- transaction_open?()
main:    -> 0.0000s
main: -- transaction_open?()
main:    -> 0.0000s
main: -- execute("ALTER TABLE protected_tag_create_access_levels\nADD CONSTRAINT fk_386a642e13\nFOREIGN KEY (deploy_key_id)\nREFERENCES keys (id)\n\nON DELETE CASCADE\nNOT VALID;\n")
main:    -> 0.0014s
main: -- execute("SET statement_timeout TO 0")
main:    -> 0.0003s
main: -- execute("ALTER TABLE protected_tag_create_access_levels VALIDATE CONSTRAINT fk_386a642e13;")
main:    -> 0.0012s
main: -- execute("RESET statement_timeout")
main:    -> 0.0003s
main: -- transaction_open?()
main:    -> 0.0000s
main: -- view_exists?(:postgres_partitions)
main:    -> 0.0006s
main: -- index_exists?(:protected_tag_create_access_levels, :deploy_key_id, {:name=>"index_protected_tag_create_access_levels_on_deploy_key_id", :algorithm=>:concurrently})
main:    -> 0.0050s
main: -- add_index(:protected_tag_create_access_levels, :deploy_key_id, {:name=>"index_protected_tag_create_access_levels_on_deploy_key_id", :algorithm=>:concurrently})
main:    -> 0.0042s
main: == 20230124193917 AddIndexForProtectedTagCreateAccessLevels: migrated (0.1591s)

Down

main: == 20230124193917 AddIndexForProtectedTagCreateAccessLevels: reverting ========
main: -- remove_foreign_key(:protected_tag_create_access_levels, {:column=>:deploy_key_id})
main:    -> 0.0033s
main: -- transaction_open?()
main:    -> 0.0000s
main: -- view_exists?(:postgres_partitions)
main:    -> 0.0009s
main: -- indexes(:protected_tag_create_access_levels)
main:    -> 0.0032s
main: -- execute("SET statement_timeout TO 0")
main:    -> 0.0004s
main: -- remove_index(:protected_tag_create_access_levels, {:algorithm=>:concurrently, :name=>"index_protected_tag_create_access_levels_on_deploy_key_id"})
main:    -> 0.0019s
main: -- execute("RESET statement_timeout")
main:    -> 0.0013s
main: == 20230124193917 AddIndexForProtectedTagCreateAccessLevels: reverted (0.1239s)

main: == 20230124122143 AddDeployKeyIdToCreateAccessLevels: reverting ===============
main: -- remove_column(:protected_tag_create_access_levels, :deploy_key_id)
main:    -> 0.0032s
main: == 20230124122143 AddDeployKeyIdToCreateAccessLevels: reverted (0.0066s) ======

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.