Fix chronik with no IPv6

Summary:
The whole test test_framework assumes that IPv6 might be disabled, but
chronik binds to ::1 by default which will cause the tests to fail.
Also the chronik_serve test checks for IPv6 support before testing the
connection, but not before binding.
This diff fixes both by moving the IPv6 support check and disabling the
IPv6 binding by default.

Test Plan:

ninja check-functional

Reviewers: #bitcoin_abc, PiRK

Reviewed By: #bitcoin_abc, PiRK

Differential Revision: https://reviews.bitcoinabc.org/D13434