框架偷偷调用了业务请求的toString方法

https://github.com/apache/servicecomb-java-chassis/blob/a23824a8e6f89f741785d144b45e30b37449311c/core/src/main/java/org/apache/servicecomb/core/governance/MatchType.java#L78

这里会调用业务请求的toString方法， 实际过程不需要，
1. 会影响业务的性能。
2. 当业务toString方法不当存在异常时，业务关闭日志打印后，依然会在这里执行toString方法产生调用异常

Start by inspecting core/src/main/java/org/apache/servicecomb/core/governance/MatchType.java around line 78 and trace why the business request's toString method is invoked. Verify the behavior with the existing project tests or a focused reproduction. Done means request matching no longer causes this unnecessary invocation or the resulting exception path.

Written by the indexing model from the issue text.