I don’t know about you, but it’s pretty obvious to me that
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is a bit too long for a filename, and definitely too long for a valid filename.
Since it’s one of the secret values, it should be pretty obvious for you where it comes from.
I would guess that it’s the value of the KUBECONFIG envvar, and it’s a mystery to me why you thought this would a be a valid value for it.
The guide that you’ve linked to has absolutely no mention of assigning such monstrous values to variables.
Likewise, as I mentioned, there’s absolutely no reason for KUBECONFIG to be a secret variable.