Is your feature request related to a problem? Please describe.
https://github.com/dapr/go-sdk/blob/main/actor/state/state_manager.go is the only file in the state directory without tests. We should add tests to improve test coverage here.

Describe the solution you'd like
We need a state_manager_test.go file added testing the functionality of the stateManagerCtx.

Additional context
You can refer to the other test files in the state directory for inspiration and guidance to setup the tests for the state_manager_test.go.