Removed expected_condition from test_add_projectfile_direct function.

Sometimes editor-loading-screen disappeared very quickly and we couldn't locate the element.
This had as result that test failed. Now we wait only for editor-loading-screen to be invisible.

Author: konstantina

tests/common/sketch/test_sketch.py

@@ -112,11 +112,6 @@ def test_add_projectfile_direct(self):
         """ Tests that new file can be added to project using create-new-file
         field """
         self.open_project()
-        WebDriverWait(self.driver, VERIFY_TIMEOUT).until(
-            expected_conditions.visibility_of_element_located(
-                (By.CSS_SELECTOR, "#editor-loading-screen")
-                )
-            )
         WebDriverWait(self.driver, VERIFY_TIMEOUT).until(
             expected_conditions.invisibility_of_element_located(
                 (By.CSS_SELECTOR, "#editor-loading-screen")