False positive insufficient fee warning

[kyranjamie]

Nick from Gamma reported seeing the insufficient balance warning, despite having sufficient balance.

@fbwoolf and I invested this last week, but were unable to replicate the issue. It did however reveal https://github.com/leather-wallet/extension/issues/5362

[markmhendrickson]

Per the Slack thread, this warning seems to appear when the fee is still loading, which is taking a long time in undiagnosed circumstances.

[markmhendrickson]