Move TI setNote endpoints under TaskInstance in OpenAPI (#28566)

These endpoints were accidentally under DAG instead of TaskInstance
where they belong.

(cherry picked from commit b3e2656)

airflow/api_connexion/openapi/v1.yaml

@@ -599,7 +599,7 @@ paths:
         *New in version 2.5.0*
       x-openapi-router-controller: airflow.api_connexion.endpoints.task_instance_endpoint
       operationId: set_task_instance_note
-      tags: [DAG]
+      tags: [TaskInstance]
       requestBody:
         description: Parameters of set Task Instance note.
         required: true
@@ -639,7 +639,7 @@ paths:
         *New in version 2.5.0*
       x-openapi-router-controller: airflow.api_connexion.endpoints.task_instance_endpoint
       operationId: set_mapped_task_instance_note
-      tags: [DAG]
+      tags: [TaskInstance]
       requestBody:
         description: Parameters of set Task Instance note.
         required: true