Allow multiple activity types per single plugin

Closes #3466156

config/activity_answer/lms_long_answer/core.entity_form_display.lms_activity._activity_type_.default.yml

 status: true
 dependencies:
   config:
-    - field.field.lms_activity.lms_long_answer.description
-    - field.field.lms_activity.lms_long_answer.question
-    - lms.lms_activity_type.lms_long_answer
-id: lms_activity.lms_long_answer.default
+    - field.field.lms_activity._activity_type_.description
+    - field.field.lms_activity._activity_type_.question
+    - lms.lms_activity_type._activity_type_
+id: lms_activity._activity_type_.default
 targetEntityType: lms_activity
-bundle: lms_long_answer
+bundle: _activity_type_
 mode: default
 content:
   description: