* format pipeline output and check it * fix UT * add docstr to clarify the difference between model.postprocess and pipeline.postprocess Link: https://code.alibaba-inc.com/Ali-MaaS/MaaS-lib/codereview/9051405
* add dockerfile * uninstall opencv-python-headless * update develop doc Link: https://code.alibaba-inc.com/Ali-MaaS/MaaS-lib/codereview/9020302