Use firefox instead of chromium

Author: manykarim

tests/01/todo/todo.robot

@@ -7,7 +7,7 @@ Test Teardown    Close Context
 Suite Teardown    Close Browser
 
 *** Variables ***
-${BROWSER}    chromium
+${BROWSER}    firefox
 ${HEADLESS}    True
 
 *** Test Cases ***
@@ -53,4 +53,4 @@ Open ToDos should show "${text}"
     Get Text    span.todo-count    ==    ${text}
 
 I Mark ToDo "${todo}"
-    Click    "${todo}" >> .. >> input.toggle
+    Click    "${todo}" >> .. >> input.toggle