A dependence bot belonging to Kmesh

[LiZhenCheng9527]

What would you like to be added:

Why is this needed:
Because Kmesh uses istiod as a control plant. When an istio-related package is updated, Kmesh needs to be synchronised as well. For example #346
This is something that would be time-consuming and labour-intensive to synchronise manually. So we need a dependency bot to handle this aspect.