add comment about null initializer in Base (#2249)

Author: joelhawksley

lib/view_component/base.rb

@@ -195,6 +195,8 @@ def render?
       true
     end
 
+    # Override the ActionView::Base initializer so that components
+    # do not need to define their own initializers.
     # @private
     def initialize(*)
     end