Import tasks from other roles in a better way

One that doesn't trip up ansible-lint, causing `load-failure` errors.

roles/matrix-registration/tasks/setup_install.yml

@@ -24,7 +24,9 @@
                 - ALTER TABLE tokens ALTER COLUMN ex_date TYPE TIMESTAMP WITHOUT TIME ZONE;
               additional_psql_statements_db_name: "{{ matrix_registration_database_name }}"
 
-        - ansible.builtin.import_tasks: "{{ role_path }}/../matrix-postgres/tasks/util/migrate_db_to_postgres.yml"
+        - ansible.builtin.import_role:
+            name: matrix-postgres
+            tasks_from: migrate_db_to_postgres
 
         - ansible.builtin.set_fact:
             matrix_registration_requires_restart: true