[BUG] WARNING Cannot find method

## Issue Description

Type: *bug report*

### Describe what happened
@SentinelResource 配置了带Throwable参数的defaultFallback方法，sentinel有时会告警找不到对应的默认方法：WARNING Cannot find method，非必现

### Describe what you expected to happen
预期无告警，且发生熔断后能走到defaultFallback降级逻辑

### How to reproduce it (as minimally and precisely as possible)

1. @SentinelResource
2. defaultFallback 带Throwable参数 ，和原方法在同一个类中，返回值为Object

### Tell us your environment
test

### Anything else we need to know?

Start with the minimal @SentinelResource case described: a same-class defaultFallback method with a Throwable parameter and Object return type. Reproduce the intermittent “Cannot find method” warning and compare runs where fallback succeeds or fails. Done means the warning is absent and circuit breaking reaches the defaultFallback logic.

Written by the indexing model from the issue text.