Don't use responsediff for json

src/memopol/tests/response_fixtures/ChartViewsTest.test_chamber_score.content

-{"chamber": "European Parliament", "scores": [-1312.0, -1216.0, -1216.0, -1216.0, -1216.0, -1216.0, -1216.0, -1208.0, -1200.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1208.0, 1224.0, 1468.0, 1468.0, 1480.0]}
\ No newline at end of file

src/memopol/tests/response_fixtures/ChartViewsTest.test_chamber_score.metadata

-{
-    "status_code": 200
-}
\ No newline at end of file

src/memopol/tests/response_fixtures/ChartViewsTest.test_theme_score.content

-{"theme": "Etat d'urgence", "scores": [-305.0, -305.0, -265.0, -235.0, -220.0, -215.0, -205.0, -205.0, -195.0, -195.0, -190.0, -185.0, -135.0, -115.0, -110.0, -105.0, -100.0, -100.0, -100.0, -90.0, -90.0, -90.0, -90.0, -55.0, -25.0, -5.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 35.0]}
\ No newline at end of file

src/memopol/tests/response_fixtures/ChartViewsTest.test_theme_score.metadata

-{
-    "status_code": 200
-}
\ No newline at end of file

src/memopol/tests/test_chart_data.py

+import json
+
 from .base import BaseTest
 
 
 class ChartViewsTest(BaseTest):
     def test_theme_score(self):
         url = '/charts/data/theme-scores/1/'
-        self.request_test(url)
+
+        data = json.loads(self.client.get(url).content)
+        expected = {
+            "theme": "Etat d'urgence",
+            "scores": [-305.0, -305.0, -265.0, -235.0, -220.0, -215.0, -205.0,
+                       -205.0, -195.0, -195.0, -190.0, -185.0, -135.0, -115.0,
+                       -110.0, -105.0, -100.0, -100.0, -100.0, -90.0, -90.0,
+                       -90.0, -90.0, -55.0, -25.0, -5.0, 0.0, 0.0, 0.0, 0.0,
+                       0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
+                       0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
+                       0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 35.0]
+        }
+
+        assert data == expected
 
     def test_chamber_score(self):
         url = '/charts/data/chamber-scores/1/'
-        self.request_test(url)
+
+        data = json.loads(self.client.get(url).content)
+        expected = {
+            "chamber": "European Parliament",
+            "scores": [-1312.0, -1216.0, -1216.0, -1216.0, -1216.0, -1216.0,
+                       -1216.0, -1208.0, -1200.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0,
+                       0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 0.0, 1208.0,
+                       1224.0, 1468.0, 1468.0, 1480.0]
+        }
+
+        assert data == expected
 
     def test_theme_score_queries(self):
         url = '/charts/data/theme-scores/1/'