Create separate feature flag for require_organization for Project Model

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Related to #501257 (closed)

app/models/application_record.rb

@@ -138,12 +138,6 @@ def self.nullable_column?(column_name)
       !not_null_check?(column_name)
   end
 
-  def require_organization?
-    return false unless Feature.enabled?(:require_organization, Feature.current_request)
-
-    Gitlab::SafeRequestStore.fetch(:require_organization) { true } # rubocop:disable Style/RedundantFetchBlock -- This fetch has a different interface
-  end
-
   def readable_by?(user)
     Ability.allowed?(user, "read_#{to_ability_name}".to_sym, self)
   end