optimize: add global descriptor release api

[wujunyi792]

Description

Add ReleaseGlobalDescriptors func to release global Descriptor

Motivation and Context

We use thrift_reflection in server to parse thrift files. However, as time goes by, the server will crash due to OOM, the root cause is that the globalDescriptorMap only increases but never decreases. Therefore, an API is needed to clean up the unused GD.

Related Issue

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