Select: Make button locator more speciffic

When there is an item selected it would click on the clear button
instead of the toggle button when trying to access items or calling
open(), this fixes that.

src/widgetastic_patternfly5/components/menus/select.py

@@ -19,7 +19,7 @@ class BaseSelect:
     https://www.patternfly.org/components/menus/select
     """
 
-    BUTTON_LOCATOR = ".//button"
+    BUTTON_LOCATOR = ".//button[contains(@class, '-c-select__toggle-button')]"
     ITEMS_LOCATOR = (
         ".//ul[contains(@class, '-c-menu__list') or contains(@class, '-c-select__menu')]/"
         "li[contains(@class, '-c-menu__list-item') or contains(@class, '-c-select__menu-wrapper')]"