Consolidate enrollment_api code

These functions were really only 1 line long and each only used once,
so let's just inline them.

openedx/stanford/common/djangoapps/enrollment/views.py

@@ -31,19 +31,6 @@
 from openedx.stanford.common.djangoapps.enrollment.data import get_roster
 
 
-def _enroll(course_key, email, auto_enroll, email_students, email_params, language):
-    enroll_email(
-        course_key, email, auto_enroll, email_students, email_params, language=language
-    )
-    return Response(status=status.HTTP_204_NO_CONTENT)
-
-def _unenroll(course_key, email, email_students, email_params, language):
-    unenroll_email(
-        course_key, email, email_students, email_params, language=language
-    )
-    return Response(status=status.HTTP_204_NO_CONTENT)
-
-
 class EnrollmentRosterView(APIView, ApiKeyPermissionMixIn):
     """
     Read roster for a particular course. (contains PII)
@@ -127,7 +114,10 @@ def put(self, request, course_id):
             if User.objects.filter(email=email).exists():
                 user = User.objects.get(email=email)
                 language = get_user_email_language(user)
-        return _enroll(course_key, email, auto_enroll, email_students, email_params, language)
+        enroll_email(
+            course_key, email, auto_enroll, email_students, email_params, language=language
+        )
+        return Response(status=status.HTTP_204_NO_CONTENT)
 
     def delete(self, request, course_id):
         """
@@ -179,4 +169,7 @@ def delete(self, request, course_id):
             if User.objects.filter(email=email).exists():
                 user = User.objects.get(email=email)
                 language = get_user_email_language(user)
-        return _unenroll(course_key, email, email_students, email_params, language)
+        unenroll_email(
+            course_key, email, email_students, email_params, language=language
+        )
+        return Response(status=status.HTTP_204_NO_CONTENT)