Fix Incorrect Command Cooldown Storage Warning

[erenkarakal]

Problem

Using the code:

command /rtp:
  cooldown: 5 minutes
  cooldown storage: {rtp.command::%player's uuid%}
  trigger:
    stop

The command would always print a warning saying Variable {var} was not a date! You may be using this variable elsewhere because it doesn't check if the variable is set first

Solution

Added a != null check

Testing Completed

Manually tested to verify the issue is solved

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Completes: none
Related: https://discord.com/channels/135877399391764480/836220422223036467/1444729250224672979

[APickledWalrus]

Seems fine