[Bug]: Import statements in test cases look for pip-installed packages when running pytest

**Describe the bug**
The import statements in test cases look for pip-installed packages when running pytest. The classes and functions should be import from the src/ folder.

**To Reproduce**
1. Make sure the agentscoe package is not installed on this machine. (pip list|grep -i agentscoe should yield nothing)
2. Run git clone to download the repository to a dev machine.
3. Run pytest resulted in import failures.