Avoid "Overwriting existing method open" warning

In Ruby, the Kernel class defined the `open` method, which is available
for (almost) every object. So creating a scope with the name `open`
generates a warning indicating we are overwriting the existing `open`
method.

While this warning is pretty much harmless and we could ignore it, it
generates a lot of noise in the logs. So I'm "undefining" the method
before generating the scope, so we don't get the warning all the time.

app/models/budget.rb

@@ -55,6 +55,7 @@ class Budget < ApplicationRecord
   scope :reviewing_ballots, -> { where(phase: "reviewing_ballots") }
   scope :finished, -> { where(phase: "finished") }
 
+  class << self; undef :open; end
   scope :open, -> { where.not(phase: "finished") }
 
   def self.current

app/models/legislation/process.rb

@@ -54,6 +54,7 @@ class Legislation::Process < ApplicationRecord
   validates :background_color, format: { allow_blank: true, with: CSS_HEX_COLOR }
   validates :font_color, format: { allow_blank: true, with: CSS_HEX_COLOR }
 
+  class << self; undef :open; end
   scope :open, -> { where("start_date <= ? and end_date >= ?", Date.current, Date.current) }
   scope :active, -> { where("end_date >= ?", Date.current) }
   scope :past, -> { where("end_date < ?", Date.current) }