fix: Update requirements-base.txt in yolo (#629)

Author: makseq

label_studio_ml/examples/yolo/requirements-base.txt

@@ -1,3 +1,3 @@
 gunicorn==22.0.0
-label-studio-ml @ git+https://github.com/HumanSignal/label-studio-ml-backend.git@feat/rnd-118
+label-studio-ml @ git+https://github.com/HumanSignal/label-studio-ml-backend.git@master
 label-studio-sdk @ git+https://github.com/HumanSignal/label-studio-sdk.git