[InterNetNews/inn] 024dbc: Developer docs/experience improvements

[Richard Kettlewell]

  Branch: refs/heads/main
  Home:   https://github.com/InterNetNews/inn
  Commit: 024dbc49e21cc0cb0f5c08a0b3894c145132fc43
      https://github.com/InterNetNews/inn/commit/024dbc49e21cc0cb0f5c08a0b3894c145132fc43
  Author: Richard Kettlewell <rjk at greenend.org.uk>
  Date:   2021-09-18 (Sat, 18 Sep 2021)

  Changed paths:
    M doc/pod/hacking.pod
    M support/mkmanifest

  Log Message:
  -----------
  Developer docs/experience improvements

- document how to run a CI build locally
- ignore .vscode local settings when creating manifest