Holding left click to attack mobs only attacks once then stops.

I was expecting to be able to hold left click to continue to attack, just as holding left click when mining continues to break blocks.

Steps to Reproduce: (Windows 10 + Mouse)

• Approach any mob
• Hold left click to attack
• Notice that you can only hit once, holding left click will not hit that or any other mob again.

May be related to MCPE-13196 and MCPE-13006