Adding a comment to help with maintainability of `app/views/org_admin/conditions/_form.html.erb`

- #3497 introduces `<% condition ||= nil %>` on line 6.
- This refactor replaces the usage of `condition_exists` with `condition.present?`
- `app/views/org_admin/conditions/_container.html.erb` appears to be the only `app/views/org_admin/conditions/_form.html.erb` that passes the `locals : { condition` variable. The `<% condition ||= nil %>` code on line 6 should be sufficient for performing this check.
- Additionally, if `condition == nil` and `condition_exists == true` ever occurred, then we would encounter `NoMethodError` exceptions on lines 13 and 27.

- `<%= select_tag(:action_type, options_for_select(action_type_arr, type_default)` was only being executed when `if condition.nil?` was true (now line 20). Additionally, that was the only line that was using the `type_default` variable.
  - Thus, no conditional is required for the assigning of `type_default` and we can just use `:remove` explicitly on line 30 now.

The modified code was and is only executed when `condition.nil?` is true (line 20). Thus, the ternary operator always evaluated to the else.

- Line 35 is the only that uses the `remove_question_group` variable. However, line 35 is only executed when `condition.nil? == true` (line 18).

This change refactors `app/views/org_admin/conditions/_form.html.erb`. The change moves the logic for new conditions to `app/views/org_admin/conditions/_new_condition_form.erb` and existing conditions to `app/views/org_admin/conditions/_existing_condition_display.erb`.

-  ` action_type_arr` and `remove_question_group` are only needed in `conditions/_new_condition_form.erb`. The assignments have been moved directly to that partial.
- -  ` view_email_content_info` is only needed in `conditions/_new_condition_form.erb`. The assignment has been moved directly to that partial.