Message on return from Stripe Connect is not formatted

Weird, this only happens with D11, the attached patch should do the trick.
Also, perhaps we should address ✨ Add a setting to suppress the credentials message after Stripe Connect Active from this MR too... Not sure anyone would ever set the settings flag though... So maybe we should not output the credentials at all? But I'm thinking this is necessary for people used to overridding credentials from settings.php (or via variables overrides from the different hosting providers).