Workbench server support cluster mode

Workbench Server is mainly for Submarine Workbench WEB is mainly for algorithm users to provide algorithm development, Python/Spark interpreter operation and other services through Notebook.

The workbench server allows multiple workbench servers to form a service cluster by integrating the cluster components.

The goal of the Submarine project is to provide high availability and high reliability services for big data processing, algorithm development, job scheduling, job scheduling, model online services, model batch and incremental updates. In addition to the high availability of big data and machine learning frameworks, the high availability of Submarine Server and Workbench Server itself is a key consideration.

Design Doc: https://docs.google.com/document/d/1Ax6FQ5CAP-jowm2_Mp2r5kc9r7s1bkFLRfzvvbm5Wzc/edit#