[BUGFIX] fix weapons swap crash dw -> 2h

[Polynomix]

fixes #359

[fredrick-a-n]

Doing a weapon swap from dw to 2h on frost dk with this change seems to lead to:
[Player 1] No available actions!
In the results log, leading to all damage done by the player to become NaN

Example:
test.txt

[Polynomix]

@fredrick-a-n can you link your setup ? I dont have your issue

[fredrick-a-n]

@fredrick-a-n can you link your setup ? I dont have your issue

@Polynomix The txt I linked has the json import for the setup, but here is a link for if you're locally hosting the branch.
http://127.0.0.1:8080/mop/death_knight/frost/#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