fix: Update input handlers with new Salesforce lightning-primitive tags (#3822)

Update `form_handlers.py` to reflect changes to Salesforce's html tags
for checkboxes and form inputs. The new tags changed from
`lightning-input` to `lightning-primitve-input-checkbox` and
`lightning-primitive-input-simple`.

Fixes #3657

Author: chanyahn-st

cumulusci/robotframework/form_handlers.py

@@ -160,7 +160,12 @@ def clear(self):
 class LightningInputHandler(BaseFormHandler):
     """An input handler for components that can be treated as an input or textarea"""
 
-    tags = ["lightning-input", "lightning-textarea", "lightning-datepicker"]
+    tags = [
+        "lightning-primitive-input-checkbox",
+        "lightning-primitive-input-simple",
+        "lightning-textarea",
+        "lightning-datepicker",
+    ]
 
     def set(self, value):
         self.focus()