v2.0: fix audit (backport of #4014)

[mergify]

Problem

the audit failed. we need to upgrade idna to >= 1.0.0. however, the dep chain looks like:

jsonrpc-core-client v18.0.0 -> jsonrpc-client-transports v18.0.0 -> url v1.7.2 -> idna v0.1.5

and jsonrpc-core-client has not released any new version in the past 3y ...

Summary of Changes

ignore it as a stopgap

---

This is an automatic backport of pull request #4014 done by Mergify.

[mergify]

Cherry-pick of 6c86ce5 has failed:

On branch mergify/bp/v2.0/pr-4014
Your branch is up to date with 'origin/v2.0'.

You are currently cherry-picking commit 6c86ce59aa.
  (fix conflicts and run "git cherry-pick --continue")
  (use "git cherry-pick --skip" to skip this patch)
  (use "git cherry-pick --abort" to cancel the cherry-pick operation)

Unmerged paths:
  (use "git add <file>..." to mark resolution)
	both modified:   ci/do-audit.sh

no changes added to commit (use "git add" and/or "git commit -a")

To fix up this pull request, you can check it out locally. See documentation: https://docs.github.com/en/pull-requests/collaborating-with-pull-requests/reviewing-changes-in-pull-requests/checking-out-pull-requests-locally