error handling in AddNewStock Buttons and UpdateStock Buttons
Merge branch 'Gayan' of https://github.com/Kasunucsc/MotorYardInventory into Kasun

# By GayanBandara
# Via GayanBandara
* 'Gayan' of https://github.com/Kasunucsc/MotorYardInventory:
  error handling in AddNewStock Buttons and UpdateStock Buttons