decode() bytes for saving into config.ini

[p0psicles]

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Fix #8810

[p0psicles]

@medariox the scecrets where stored as "binary". Like "b'sakljdflskdjflkdsjflksdfjldskjf'"
I suspect this was the issue. But should we create a config migration for this?

[medariox]

Hmm, I think there is something wrong with encode() and decode()... like the secret is getting decoded and encoded again, although it shouldn't if it is already encoded.

[medariox]

@p0psicles
No need for a migration as b'asasqqwqwe' and asasqqwqwe are both valid secrets. New installs won't have the b' prefix tho.