Prevent running vaex tests if vaex isn't installed

Author: marthacryan

Diff for: tests/test_optional/test_px/test_px_input.py

@@ -14,8 +14,7 @@
 import warnings
 
 
-# FIXME: don't test with vaex if vaex isn't installed
-if (optional_imports.get_module("vaex") is None) and (sys.version_info >= (3, 12)):
+if (optional_imports.get_module("vaex") is None):
     TEST_LIBS = ["polars"]
 else:
     TEST_LIBS = ["vaex", "polars"]