Update `lightninglabs/loopserver`/`regtest`

[linden]

Is your feature request related to a problem? Please describe.

Currently lightninglabs/loopserver/regtest does not support Static Loop In Addresses or Instant Loop Outs.

Describe the solution you'd like

Updating lightninglabs/loopserver would be very helpful for testing these features.

Describe alternatives you've considered

N/A

Additional context

I'm working on an alternative Loop server, I'm testing against the lightninglabs/loopserver to ensure compatibility.

[hieblmi]

Static address support has been added.