(#16) fix put lesson api call

stubs/api/index.js

@@ -49,7 +49,7 @@ router.delete('/lesson/:lessonId', (req, res) => {
   res.send({ success: true, body: { ok: true }})
 })
 
-router.put('/lesson/:lessonId', (req, res) => {
+router.put('/lesson', (req, res) => {
   res.send({ success: true, body: req.body })
 })