improve autopilot logging when it starts up

[raskchanky]

Description

While dealing with an autopilot escalation, I noticed that the logging when autopilot starts up is suboptimal, for a few reasons.

• The struct that is written to the logs is fairly useless, as you only see values, not struct member names
• If the autopilot reconcile interval hasn't been modified via the config (which is the case the overwhelming majority of the time, I imagine) then reconcile_interval 0s is printed to the logs, which is incorrect, and actually alarming. What's happening is it's printing out the value of the reconcile interval as it exists on the raft backend, which is 0 by default, but that's not actually the value autopilot is using. This is misleading.

This makes the autopilot config struct print in a better way and also updates the logging to not actually print the values for reconcile interval or update interval unless they were actually changed from their defaults.

TODO only if you're a HashiCorp employee

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  of a public function, even if that change is in a CE file, double check that
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  break any tests. Sometimes ENT only tests rely on public functions in CE
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