Apply Layout/LineLength rubocop rule

Note we're excluding a few files:

* Configuration files that weren't generated by us
* Migration files that weren't generated by us
* The Gemfile, since it includes an important comment that must be on
  the same line as the gem declaration
* The Budget::Stats class, since the heading statistics are a mess and
  having shorter lines would require a lot of refactoring

spec/system/officing/ballot_sheets_spec.rb

@@ -23,7 +23,8 @@ describe "Officing ballot sheets" do
     within("tr", text: "Latest budget poll") { click_link "Add results" }
 
     select "The only booth", from: "Booth"
-    fill_in "CSV data", with: "#{investments[0..1].map(&:id).join(",")};#{investments[1..2].map(&:id).join(",")}"
+    fill_in "CSV data",
+            with: "#{investments[0..1].map(&:id).join(",")};#{investments[1..2].map(&:id).join(",")}"
     click_button "Save"
 
     expect(page).to have_content "Creation date"

spec/system/officing/results_spec.rb

@@ -91,7 +91,9 @@ describe "Officing Results", :with_frozen_time do
       amount: 7777
     )
 
-    visit officing_poll_results_path(poll, date: I18n.l(partial_result.date), booth_assignment_id: partial_result.booth_assignment_id)
+    visit officing_poll_results_path(poll,
+                                     date: I18n.l(partial_result.date),
+                                     booth_assignment_id: partial_result.booth_assignment_id)
 
     within("#question_#{question_1.id}_0_result") { expect(page).to have_content("7777") }
 

spec/system/officing/voters_spec.rb

@@ -68,7 +68,10 @@ describe "Voters" do
   end
 
   scenario "Had already verified his residence, but is not level 2 yet" do
-    user = create(:user, residence_verified_at: Time.current, document_type: "1", document_number: "12345678Z")
+    user = create(:user,
+                  residence_verified_at: Time.current,
+                  document_type: "1",
+                  document_number: "12345678Z")
     expect(user).not_to be_level_two_verified
 
     visit root_path