setEndpointMockState
Sets the mock state for a specific endpoint identified by an EndpointKey.
When responseFileName is null, the endpoint state is set to EndpointMockState.Network, effectively disabling mocking for that endpoint.
When responseFileName is non-null, the endpoint transitions to EndpointMockState.Mock with the given file, replacing any previous state.
Parameters
key
The EndpointKey identifying the group, environment, and endpoint
responseFileName
The response file to use for mocking, or null to use the actual network