How to manage HTTP "accounts" in Pipelines

I'm using the HTTP "Make Request" step in several pipelines to make HTTP calls from Quickbase to my applications API.  The way you configure the URL and authentication information for that API is via the "Connection" where you configure an "HTTP account".  I can see how to create a new "account" there, but I can't figure out where to update or delete those accounts.  I've searched the Quickbase UI and couldn't find anything, and the docs didn't contain anything that I could find.  I considered using "variables" to try to specify my URL and reference the variable in the "HTTP account", but that context doesn't seem to support variables, which seem like they were built for use in formulas, not pipelines.  Can anyone tell me how to manage (edit, delete) my HTTP accounts used in my pipelines?  Thanks!