We can't claim we have a "HIPAA compliant" reference architecture — Use "HIPAA eligible" instead

As reported in [this Slack message](https://gruntwork-io.slack.com/archives/C0275GS2FKM/p1627910644063300):
> We should call the HIPAA Ref Arch, "HIPAA eligible", as HIPAA compliance can only be conferred by an auditor.

As such we should do a scan of the language we're using to make sure we aren't overstating it. Since there's nothing contractual about the waitlist I don't think there's any potential legal ramifications yet, but it would be best to abide by the rules. We can probably talk about user's needs/goals in terms of compliance, just not our infrastructure itself, e.g. "Reach HIPAA compliance faster by building atop our HIPAA eligible reference architecture…"