Remove unnecessary code

It looks like these variables were left by accident. The Ruby
interpreter was giving us warnings about unused variables.

app/models/abilities/tracker.rb

@@ -3,8 +3,6 @@ module Abilities
     include CanCan::Ability
 
     def initialize(user)
-      tracker = user.tracker
-
       can :index, Budget
       can [:index, :show, :edit], Budget::Investment
       can :manage, Milestone

spec/features/admin/poll/shifts_spec.rb

@@ -8,7 +8,6 @@ describe "Admin shifts" do
   end
 
   scenario "Show" do
-    poll = create(:poll)
     officer = create(:poll_officer)
 
     booth1 = create(:poll_booth)
@@ -246,7 +245,6 @@ describe "Admin shifts" do
   end
 
   scenario "Destroy an officer" do
-    poll = create(:poll)
     booth = create(:poll_booth)
     officer = create(:poll_officer)
 
@@ -261,7 +259,6 @@ describe "Admin shifts" do
   end
 
   scenario "Empty" do
-    poll = create(:poll)
     booth = create(:poll_booth)
 
     visit new_admin_booth_shift_path(booth)

spec/features/admin/stats_spec.rb

@@ -388,8 +388,6 @@ describe "Stats" do
     end
 
     scenario "Participants by poll" do
-      oa = create(:poll_officer_assignment)
-
       poll1 = create(:poll)
       poll2 = create(:poll)
 

spec/features/budgets/investments_spec.rb

@@ -1760,7 +1760,6 @@ describe "Budget Investments" do
       scenario "Due to being unfeasible" do
         user = create(:user, :level_two)
         investment = create(:budget_investment, :selected, heading: heading)
-        heading2 = create(:budget_heading, group: group)
 
         ballot = create(:budget_ballot, user: user, budget: budget)
         ballot.investments << investment

spec/features/direct_messages_spec.rb

@@ -60,7 +60,6 @@ describe "Direct messages" do
     end
 
     scenario "User not logged in" do
-      sender = create(:user)
       receiver = create(:user)
 
       visit new_user_direct_message_path(receiver)

spec/features/polls/answers_spec.rb

@@ -39,12 +39,11 @@ describe "Answers" do
   end
 
   scenario "Add video to answer" do
-    answer1 = create(:poll_question_answer, question: question)
-    answer2 = create(:poll_question_answer, question: question)
+    answer = create(:poll_question_answer, question: question)
 
     visit admin_question_path(question)
 
-    within("#poll_question_answer_#{answer1.id}") do
+    within("#poll_question_answer_#{answer.id}") do
       click_link "Video list"
     end
 
@@ -55,7 +54,7 @@ describe "Answers" do
 
     click_button "Save"
 
-    within("#poll_question_answer_video_#{answer1.videos.last.id}") do
+    within("#poll_question_answer_video_#{answer.videos.last.id}") do
       expect(page).to have_content "Awesome project video"
       expect(page).to have_content "https://www.youtube.com/watch?v=123"
     end

spec/features/polls/voter_spec.rb

@@ -50,8 +50,6 @@ describe "Voter" do
     end
 
     scenario "Voting in booth", :js do
-      user = create(:user, :in_census)
-
       login_through_form_as_officer(officer.user)
 
       visit new_officing_residence_path

spec/models/poll/shift_spec.rb

@@ -58,7 +58,6 @@ describe Poll::Shift do
 
     it "creates and destroy corresponding officer_assignments" do
       poll2 = create(:poll)
-      poll3 = create(:poll)
 
       booth_assignment1 = create(:poll_booth_assignment, poll: poll, booth: booth)
       booth_assignment2 = create(:poll_booth_assignment, poll: poll2, booth: booth)

spec/models/signature_spec.rb

@@ -183,7 +183,6 @@ describe Signature do
       it "creates a user with that document number" do
         create(:geozone, census_code: "01")
         signature = create(:signature, document_number: "12345678Z")
-        proposal = signature.signable
 
         signature.verify