Fix status code for rate limit (#1924)

Co-authored-by: Rahul Bhati <rjbhati009@gmail.com>
Co-authored-by: Vishal <vishal-biyani@users.noreply.github.com>

pkg/router/functionHandler_test.go

@@ -65,5 +65,5 @@ func TestProxyErrorHandler(t *testing.T) {
 
 	respRecorder = httptest.NewRecorder()
 	errHandler(respRecorder, req, errors.New("dummy"))
-	assert.Equal(t, http.StatusBadGateway, respRecorder.Code)
+	assert.Equal(t, http.StatusInternalServerError, respRecorder.Code)
 }