add test case upload api

problem/views/oj.py

@@ -0,0 +1,8 @@
+from utils.api import APIView
+
+from ..models import ProblemTag
+
+
+class ProblemTagAPI(APIView):
+    def get(self, request):
+        return self.success([item.name for item in ProblemTag.objects.all().order_by("id")])