fix typo in run_speech_recognition_ctc.py (#21528)

Update run_speech_recognition_ctc.py

There should be `# limitations under the License` line at the end of the documentation section.

examples/pytorch/speech-recognition/run_speech_recognition_ctc.py

@@ -12,6 +12,7 @@
 # distributed under the License is distributed on an "AS IS" BASIS,
 # WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
 # See the License for the specific language governing permissions and
+# limitations under the License.
 
 """ Fine-tuning a 🤗 Transformers CTC model for automatic speech recognition"""