Assert "Trying to removbe an attribute" in Mutant Battle Arena constantly

Verification builds: Release 980905 - 1.6.0 RC0
Summary: When playing Mutant Battle Arena I get bombarded with the below assert. "Trying to remove an attribute that doesn't exist in the instance"

Repro Steps:

1. Download Mutant Battle Arena
2. Start game and wait.

Observed Results:

1. Assert pops up.
2. I suspect it has something to do with the player.json but this assert was not coming up in prior versions and everything regarding the player seems to be working correctly.

Expected Results:No asserts

Impact: This makes Mutant Battle Arena extremely arduous to test in addition to the fact there could be something under the hood that is breaking

Video: https://youtu.be/WOKEQH9HMHA

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Assert Failure - ctrl+C to copy this message to the clipboard!
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Assertion failed: Trying to remove an attribute that doesn't exist in the instance
Condition is false: false
Function: BaseAttributeMap::removeAttribute in f:\darwinwork\6\s\handheld\src\common\world\attribute\attributemap.cpp @ 52

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OK
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