re-indent template performance code snippet

docs/advanced_topics/performance.rst

@@ -74,12 +74,12 @@ The overhead from reading and compiling templates can add up. In some cases a si
         'BACKEND': 'django.template.backends.django.DjangoTemplates',
         'DIRS': [os.path.join(BASE_DIR, 'templates')],
         'OPTIONS': {
-        'loaders': [
-            ('django.template.loaders.cached.Loader', [
-            'django.template.loaders.filesystem.Loader',
-            'django.template.loaders.app_directories.Loader',
-            ]),
-        ],
+            'loaders': [
+                ('django.template.loaders.cached.Loader', [
+                    'django.template.loaders.filesystem.Loader',
+                    'django.template.loaders.app_directories.Loader',
+                ]),
+            ],
         },
     }]