Remove inherit? method from Entry::Inherit::Variables

The usage of this method was removed when implementing workflow:rules

lib/gitlab/ci/config/entry/inherit/variables.rb

@@ -13,9 +13,6 @@ module Gitlab
             strategy :ArrayStrategy, if: -> (config) { config.is_a?(Array) }
 
             class BooleanStrategy < ::Gitlab::Config::Entry::Boolean
-              def inherit?(_key)
-                value
-              end
             end
 
             class ArrayStrategy < ::Gitlab::Config::Entry::Node
@@ -25,20 +22,12 @@ module Gitlab
                 validates :config, type: Array
                 validates :config, array_of_strings: true
               end
-
-              def inherit?(key)
-                value.include?(key.to_s)
-              end
             end
 
             class UnknownStrategy < ::Gitlab::Config::Entry::Node
               def errors
                 ["#{location} should be a bool or array of strings"]
               end
-
-              def inherit?(key)
-                false
-              end
             end
           end
         end

spec/lib/gitlab/ci/config/entry/inherit/variables_spec.rb

@@ -24,19 +24,4 @@ RSpec.describe ::Gitlab::Ci::Config::Entry::Inherit::Variables do
       end
     end
   end
-
-  describe '#inherit?' do
-    where(:config, :inherit) do
-      true  | true
-      false | false
-      %w[A] | true
-      %w[B] | false
-    end
-
-    with_them do
-      it do
-        expect(subject.inherit?('A')).to eq(inherit)
-      end
-    end
-  end
 end