There are two places in LeasActiveLoadBalance that need to be optimized.

1. When calculating the total weight, we use a weight that has not been processed by warmup. When multiple invokers have the same active request and weight, we use the weight of the warmup, which is not uniform.
2. When multiple invokers have the same active request and weight, we randomly select them by weight. There is a bug here that causes the actual randomness to not be strictly weighted.

The pr to fix this two problem:
#2172

The related issue:
#904