Fix FxA state machine spelling

[bendk]

A while back we purposely misspelled "Auth" as "Ath" to get around the Sentry redaction rules. Now that we're using the error ping and Grafana we don't need this anymore.

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[skhamis]

Nice! Glad we don't have to work around this lol

[skhamis]

Lets update this too so future us ain't confused