Update a method summary

Author: mdmintz

seleniumbase/fixtures/base_case.py

@@ -3448,7 +3448,7 @@ def wait_for_attribute(
             by=By.CSS_SELECTOR, timeout=None):
         """Raises an exception if the element attribute/value is not found.
         If the value is not specified, the attribute only needs to exist.
-        Returns the element that contains the attribute.
+        Returns the element that contains the attribute if successful.
         Default timeout = LARGE_TIMEOUT."""
         self.__check_scope()
         if not timeout: