Mistake in manual upgrade instructions

Author: PetePycom

content/pylife/fwupdate/_index.md

@@ -49,7 +49,7 @@ If you want to do this, do the following:
  1) Download the relevant firmware for your PyGo. Click on the relevant link below, and download the firmware in the URL field
  * [PyGo1 firmware](https://software.pycom.io/manifest.json?sysname=pygo1&fwtype=pylife&current_ver=1.20.4)
  * [PyGo2 firmware](https://software.pycom.io/manifest.json?sysname=pygo2&fwtype=pylife&current_ver=1.20.4)
- 2) Connect to your PyGo's serial terminal, and run `update()`
+ 2) Connect to your PyGo's serial terminal, and run `upgrade()`
  3) On your computer, connect to the PyGo's access point:
  * SSID: PyCom_AP_Firmware_Update
  * Password: pycom