Bug 1868418 - Rerun ensure capabilities after logging in

[bendk]

Moved the code to RetryingAccount, which should give us this functionality for free.

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[bendk]

I think I got the state machine stuff right, but please double-check my work here.

[skhamis]

Nice fix! I think we're close but just one question about the error part

[skhamis]

One thing worth checking: in the old code we land at S::AuthIssues when check_authorization_status comes back false. The new code propagates the original FxaError::Authentication to the Err(cause) arm, which sends us to S::Disconnected?. For someone who is signed-in and whose refresh token is server-invalidated (password-changed elsewhere), I think our AuthIssues preserves the account state and lets consumers show the "re-auth" flow. Disconnected will put them back to full sign-in right?
Should we do something like:

 match account.finish_initialize(&device_config.capabilities) {
                         Ok(()) => Ok(S::Connected),
                        Err(cause) => {
                            let target = if matches!(cause.get_error_handling().err, FxaError::Authentication) {
                                S::AuthIssues
                            } else {
                                S::Disconnected
                            };
                            Err(StateMachineErr::new(cause, target))
                        }
                    }

or something similar? However if i'm missing something here please let me know!