fix: sp info endpoint - chain info always null

[jcace]

closes #905

• Fixed incorrect error handling:

if err != nil { // we should do this if err *IS* nil!
	out[i].ChainInfo = ci
}

• Also took the opportunity to speed up the querying of ChainInfo, as the request was taking 30+ seconds to run in prod. In local testing, got it down from 10 seconds to under 2 seconds.

[alvin-reyes]

LGTM

[jcace]

API Request/response screenshot