Replace all `WORKLOAD_MANAGER_ADDR` with `WORKLOAD_MANAGER_URL`

[YaoZengzeng]

In agentcube we use WORKLOAD_MANAGER_ADDR or WORKLOAD_MANAGER_URL to represent the address of workload manager.

It's confusing sometime, we should use WORKLOAD_MANAGER_URL consistently.

[acsoto]

WORKLOAD_MANAGER_URL
ROUTER_URL
REDIS_URL

[katara-Jayprakash]

/assign