Move in_browser expectations inside the same block

This way the code is easier to follow, and we avoid having simultaneous
requests on different browser sessions, which in theory shouldn't affect
the application, but the test might be a bit more robust this way.

spec/system/officing_spec.rb

@@ -117,16 +117,18 @@ describe "Poll Officing" do
     in_browser(:one) do
       login_as officer1.user
       visit officing_root_path
+
+      expect(page).to have_content "Here you can validate user documents and store voting results"
     end
 
     in_browser(:two) do
       login_as officer2.user
       visit officing_root_path
+
+      expect(page).to have_content "Here you can validate user documents and store voting results"
     end
 
     in_browser(:one) do
-      expect(page).to have_content("Here you can validate user documents and store voting results")
-
       visit new_officing_residence_path
       expect(page).to have_css "#residence_document_type"
 
@@ -148,8 +150,6 @@ describe "Poll Officing" do
     end
 
     in_browser(:two) do
-      expect(page).to have_content("Here you can validate user documents and store voting results")
-
       visit new_officing_residence_path
       expect(page).to have_css "#residence_document_type"