/v2/info only updates on burn block

[obycode]

In running the managed testnets, we realized that the /v2/info endpoint does not stay up-to-date with the current Stacks tip height. Instead it is only updating when a new burn block is processed.

[jcnelson]

Yup, that's the current design.

[jcnelson]

You can fix it by checking the canonical stacks tip instead of the burnchain tip when determining whether or not the state for /v2/info needs to be reloaded. Unfortunately I'm too behind on the network state machines to do this right this second, but if you don't feel comfortable doing it, I can fold it into one of the PRs.

[obycode]

Yup, I can take this one when I have some time.

[jcnelson]

PR sent