Removed protected_tags_array

This memorized array appears to originally come from https://gitlab.com/gitlab-org/gitlab-ee/commit/19c2c90ccac86a21eb4266b9a5972162f917f692 which has a commit message of ‘fix warnings’. Without any comments on the original pull request I think we can safely get rid of it unless warnings re-appear.

app/models/project.rb

@@ -883,16 +883,6 @@ class Project < ActiveRecord::Base
     "#{url}.git"
   end
 
-  #TODO: Check with if this is still needed, maybe because of `.select {` in ProtectedRefsMatcher
-  #Either with tests or by asking Tim
-  def protected_tags_array
-    @protected_tags_array ||= self.protected_tags.to_a
-  end
-
-  def protected_branches_array
-    @protected_branches_array ||= self.protected_branches.to_a
-  end
-
   def user_can_push_to_empty_repo?(user)
     !ProtectedBranch.default_branch_protected? || team.max_member_access(user.id) > Gitlab::Access::DEVELOPER
   end

app/models/protected_branch.rb

@@ -15,8 +15,7 @@ class ProtectedBranch < ActiveRecord::Base
   def self.protected?(project, ref_name)
     return true if project.empty_repo? && default_branch_protected?
 
-    protected_refs = project.protected_branches_array
-    self.matching(ref_name, protected_refs: protected_refs).present?
+    self.matching(ref_name, protected_refs: project.protected_branches).present?
   end
 
   def self.default_branch_protected?

app/models/protected_tag.rb

@@ -9,7 +9,6 @@ class ProtectedTag < ActiveRecord::Base
   accepts_nested_attributes_for :push_access_levels
 
   def self.protected?(project, ref_name)
-    protected_refs = project.protected_tags_array
-    self.matching(ref_name, protected_refs: protected_refs).present?
+    self.matching(ref_name, protected_refs: project.protected_tags).present?
   end
 end