Draft: Instance Integrations test of shared module code

What does this MR do and why?

Mentions #499482 (closed)

[1] pry(main)> Integrations::Instance::Jenkins.create!

=> #<Integrations::Instance::Jenkins:0x00000001561f2f28


[4] pry(main)> Integrations::Jenkins.create!(group: Group.last)

=> #<Integrations::Jenkins:0x0000000137b121e0

[1] pry(main)> Integrations::Jira.create!(group: Group.last)

=> #<Integrations::Jira:0x00000001636b5a08

[2] pry(main)> Integrations::Instance::Jira.create!

=> #<Integrations::Instance::Jira:0x0000000162812a00

[4] pry(main)> Integrations::Instance::Jira.last.jira_tracker_data

=> #<Integrations::JiraTrackerData:0x000000015ac31cd8
 id: 12,

MR acceptance checklist

Please evaluate this MR against the MR acceptance checklist. It helps you analyze changes to reduce risks in quality, performance, reliability, security, and maintainability.

Screenshots or screen recordings

Screenshots are required for UI changes, and strongly recommended for all other merge requests.

Before	After

How to set up and validate locally

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

app/models/concerns/integrations/instance/base_data_fields.rb

+# frozen_string_literal: true
+
+module Integrations
+  module Instance
+    module BaseDataFields
+      extend ActiveSupport::Concern
+
+      included do
+        belongs_to :instance_integration, inverse_of: self.table_name.to_sym, foreign_key: :instance_integration_id, class_name: 'Integrations::Instance::Integration'
+      end
+
+      class_methods do
+        def encryption_options
+          {
+            key: Settings.attr_encrypted_db_key_base_32,
+            encode: true,
+            mode: :per_attribute_iv,
+            algorithm: 'aes-256-gcm'
+          }
+        end
+      end
+
+      def activated?
+        !!instance_integration&.activated?
+      end
+
+      def to_database_hash
+        as_json(
+          only: self.class.column_names
+        ).except('id', 'service_id', 'instance_integration_id', 'created_at', 'updated_at')
+      end
+    end
+  end
+end