fix(MockResponse): added thread-safe to the MockResponse

[nomadesoft]

Summary

The PR adds thread-safety to the MockResponse struct by introducing a sync.RWMutex and ensuring that all read and write operations on the MockResponse fields are properly synchronized.

Motiviation

Prevent race conditions.

Changes

1. mocks.go:
   • Added a sync.RWMutex field mu to the MockResponse struct.
   • Wrapped read operations with RLock and RUnlock.
   • Wrapped write operations with Lock and Unlock.