add: warning on research-only model.

Author: sayakpaul

docs/source/en/api/pipelines/text_to_video.mdx

@@ -10,6 +10,12 @@ an "AS IS" BASIS, WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express o
 specific language governing permissions and limitations under the License.
 -->
 
+<Tip warning={true}>
+
+This pipeline is for research purposes only. 
+
+</Tip>
+
 # Text-to-video synthesis
 
 ## Overview