Move new budget investment view to a component

That way we'll be able to simplify some of the code.

app/components/budgets/investments/new_component.rb

@@ -0,0 +1,7 @@
+class Budgets::Investments::NewComponent < ApplicationComponent
+  attr_reader :budget
+
+  def initialize(budget)
+    @budget = budget
+  end
+end