DEV: Replace old field_type text column with field_type_enum integer column (#27448)

Follow up to: #27444. In that PR we added a new integer column for UserField#field_type and populated the data based on the old text field.

In this PR we drop the old text column and swap in the new integer (enum) column.

db/post_migrate/20240612073116_swap_field_type_with_field_type_enum_on_user_fields.rb

@@ -0,0 +1,14 @@
+# frozen_string_literal: true
+
+class SwapFieldTypeWithFieldTypeEnumOnUserFields < ActiveRecord::Migration[7.0]
+  DROPPED_COLUMNS ||= { user_fields: %i[field_type] }
+
+  def up
+    DROPPED_COLUMNS.each { |table, columns| Migration::ColumnDropper.execute_drop(table, columns) }
+    rename_column :user_fields, :field_type_enum, :field_type
+  end
+
+  def down
+    raise ActiveRecord::IrreversibleMigration
+  end
+end