Should use getDeclaredMethods instead of getMethods

#### Investigative information

Please provide the following:

- Timestamp:
- Function App name:
- Function name(s) (as appropriate):
- Invocation ID:
- Region:

#### Repro steps

Provide the steps required to reproduce the problem:

#### Expected behavior

Provide a description of the expected behavior.

#### Actual behavior

Provide a description of the actual behavior observed.

#### Known workarounds

Provide a description of any known workarounds.

#### Related information

Provide any related information

* Programming language used
* Links to source
* Bindings used

see the code here it should use getDeclaredMethods to get rid of loop unnecessary method from base class
https://github.com/Azure/azure-functions-java-worker/blob/d7819f42d8230a4e1b76f0b25cab11168b80c144/src/main/java/com/microsoft/azure/functions/worker/broker/EnhancedJavaMethodExecutorImpl.java#L25
https://github.com/Azure/azure-functions-java-worker/blob/d7819f42d8230a4e1b76f0b25cab11168b80c144/src/main/java/com/microsoft/azure/functions/worker/broker/JavaMethodExecutorImpl.java#L26

Also if only compare method name then we cannot do method reload, we should also compare method signature.