Revert "Secrets: Refactor data_key_id out of the encoded secure value payload" (#112034)

Revert "Secrets: Refactor data_key_id out of the encoded secure value payload…"

This reverts commit acad92864e.

pkg/storage/secret/encryption/testdata/mysql--encrypted_value_create-create.sql

@@ -3,7 +3,6 @@ INSERT INTO `secret_encrypted_value` (
   `name`,
   `version`,
   `encrypted_data`,
-  `data_key_id`,
   `created`,
   `updated`
 ) VALUES (
@@ -11,7 +10,6 @@ INSERT INTO `secret_encrypted_value` (
   'n1',
   1,
   '[115 101 99 114 101 116]',
-  'test-data-key-id',
   1234,
   5678
 );