remove unused statements

src/tests/test_analysis/test_gaussian_beam/test_fit_beam_data.py

 from pathlib import Path
 from unittest import TestCase
 
-import numpy as np
-
 from openqlab import io
-from openqlab.analysis.gaussian_beam import GaussianBeam, fit_beam_data
+from openqlab.analysis.gaussian_beam import fit_beam_data
 
 filedir = Path(__file__).parent