Fixed some tests.

app/Generator/Chart/Bill/BillChartGenerator.php

@@ -29,4 +29,4 @@ interface BillChartGenerator
      */
     public function frontpage(Collection $paid, Collection $unpaid);
 
-}
+}

app/Generator/Chart/Bill/ChartJsBillChartGenerator.php

@@ -80,4 +80,4 @@ class ChartJsBillChartGenerator implements BillChartGenerator
     public function single(Bill $bill, Collection $entries)
     {
     }
-}
+}

app/Generator/Chart/Bill/GoogleBillChartGenerator.php

@@ -84,4 +84,4 @@ class GoogleBillChartGenerator implements BillChartGenerator
 
         return $chart->getData();
     }
-}
+}