Update decoder.py

Author: jaeyoo

tensorflow_tts/utils/decoder.py

@@ -12,6 +12,8 @@
 # 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.
+import tensorflow as tf
+
 from tensorflow_addons.utils.types import Number
 from tensorflow_addons.utils.types import TensorLike
 from tensorflow_addons.seq2seq.decoder import (