docs: Fix broken link in Volley training am: 05dd9d2c29 am: 346114e346 am: c8c2abed0e am: 46c1d5a5d2
am: 5513b6776e

* commit '5513b6776e0b00fd0444cf4f964451d0ef61a511':
  docs: Fix broken link in Volley training

Change-Id: Ia030a066b44dfd842a8ea411001dbf454003fb20