Remove deleted SAGE_SRC feature

Author: tobiasdiez

src/sage/features/sagemath.py

@@ -1147,35 +1147,36 @@ def all_features():
         sage: list(all_features())
         [...Feature('sage.combinat'), ...]
     """
-    return [SAGE_SRC(),
-            sagemath_doc_html(),
-            sage__combinat(),
-            sage__geometry__polyhedron(),
-            sage__graphs(),
-            sage__groups(),
-            sage__libs__braiding(),
-            sage__libs__ecl(),
-            sage__libs__flint(),
-            sage__libs__gap(),
-            sage__libs__giac(),
-            sage__libs__homfly(),
-            sage__libs__linbox(),
-            sage__libs__m4ri(),
-            sage__libs__ntl(),
-            sage__libs__pari(),
-            sage__libs__singular(),
-            sage__modular(),
-            sage__modules(),
-            sage__numerical__mip(),
-            sage__plot(),
-            sage__rings__complex_double(),
-            sage__rings__finite_rings(),
-            sage__rings__function_field(),
-            sage__rings__number_field(),
-            sage__rings__padics(),
-            sage__rings__polynomial__pbori(),
-            sage__rings__real_double(),
-            sage__rings__real_mpfr(),
-            sage__sat(),
-            sage__schemes(),
-            sage__symbolic()]
+    return [
+        sagemath_doc_html(),
+        sage__combinat(),
+        sage__geometry__polyhedron(),
+        sage__graphs(),
+        sage__groups(),
+        sage__libs__braiding(),
+        sage__libs__ecl(),
+        sage__libs__flint(),
+        sage__libs__gap(),
+        sage__libs__giac(),
+        sage__libs__homfly(),
+        sage__libs__linbox(),
+        sage__libs__m4ri(),
+        sage__libs__ntl(),
+        sage__libs__pari(),
+        sage__libs__singular(),
+        sage__modular(),
+        sage__modules(),
+        sage__numerical__mip(),
+        sage__plot(),
+        sage__rings__complex_double(),
+        sage__rings__finite_rings(),
+        sage__rings__function_field(),
+        sage__rings__number_field(),
+        sage__rings__padics(),
+        sage__rings__polynomial__pbori(),
+        sage__rings__real_double(),
+        sage__rings__real_mpfr(),
+        sage__sat(),
+        sage__schemes(),
+        sage__symbolic(),
+    ]