Update eval_performance.py (#50679)

I think there is someone has forgotten or maybe delete this by mistaken : import numpy as np

Author: casadipietra

doc/scripts/eval_performance.py

@@ -6,6 +6,7 @@
 from pandas import DataFrame
 
 setup_common = """from pandas import DataFrame
+import numpy as np
 df = DataFrame(np.random.randn(%d, 3), columns=list('abc'))
 %s"""