Prune duplicate commands

[NBKelly]

Essentially, if some packets are slowed down in transit, or there's a holdup, and we end up clicking draw again, sometimes after 3-4 seconds we suddenly draw 2 cards. What this does it asserts, when receiving a game action, that we haven't made another game action within the last 30ms. That should solve most of these issues (where the issue is the packet making it to the server, rather than the packet making it back), and should also solve double-clicking mice.

We can do most of the work to fix lag, but there will always be random path issues for random users at random times, or users with spotty connections, so this will always be relevant.

From my testing, this works fine, but right now it makes every single unit test in the game fail, so there's clearly something significant I need to change :joy:

Closes #5213