Update specs to new rspec syntax

spec/integration/api/cross_origin_request_spec.rb

@@ -22,12 +22,12 @@ feature 'API cross origin request' do
       { 'Origin' => origin }
     )
 
-    response.headers['Access-Control-Allow-Origin'].should == origin
-    response.headers['Access-Control-Allow-Credentials'].should == 'true'
-    response.headers['Access-Control-Allow-Methods'].should ==
-      'GET, POST, PUT, DELETE'
-    response.headers['Access-Control-Allow-Headers'].should ==
-      'Content-Type, Content-Length, X-Requested-With'
+    expect(response.headers['Access-Control-Allow-Origin']).to eq origin
+    expect(response.headers['Access-Control-Allow-Credentials']).to eq 'true'
+    expect(response.headers['Access-Control-Allow-Methods'])
+      .to eq 'GET, POST, PUT, DELETE'
+    expect(response.headers['Access-Control-Allow-Headers'])
+      .to eq 'Content-Type, Content-Length, X-Requested-With'
   end
 
   scenario 'basic request' do
@@ -36,15 +36,16 @@ feature 'API cross origin request' do
       'Origin' => origin
     }
 
-    response.headers['Access-Control-Allow-Origin'].should == origin
-    response.headers['Access-Control-Allow-Credentials'].should == 'true'
-    response.headers['Access-Control-Expose-Headers'].should == 'Content-Length'
+    expect(response.headers['Access-Control-Allow-Origin']).to eq origin
+    expect(response.headers['Access-Control-Allow-Credentials']).to eq 'true'
+    expect(response.headers['Access-Control-Expose-Headers'])
+      .to eq 'Content-Length'
   end
 
   scenario 'request without origin' do
     # FIXME: replace with a more stable/generic action
     get api_playlists_path(format: :json)
 
-    response.headers['Access-Control-Allow-Origin'].should == ''
+    expect(response.headers['Access-Control-Allow-Origin']).to eq ''
   end
 end