stubby: Update to 0.4.3

stubby: Update to 0.4.3

Changelog from upstream (https://github.com/getdnsapi/stubby/blob/v0.4.3/ChangeLog):

* 2022-12-22: version 0.4.3
  * Fix Issue getdnsapi/stubby#330 and PR getdnsapi/stubby#324: PrivateUsers=false needed in systemd
    stubby.service file for stubby to start.
    Thanks Archcan and Petr Menšík
  * PR getdnsapi/stubby#323: Reduce log messages when interface is offline.
    Thanks Russ Bubley and Andre Heider

* 2022-08-19: version 0.4.2
  * Fix Issue getdnsapi/stubby#320: Stubby doesn't start without "log_level"
    entry. Thanks Johnny S. Lee

* 2022-08-19: Version 0.4.1
  * Several updates to the servers in the config file:
     * sinodun.dnsovertls*.com servers are removed and will be
       decommissioned in the near future. This leaves only the
       getdnsapi.net server as the default.
       A recommendation is made that users choose additional servers
       from the list available.
     * Additional Quad9 servers added (thanks pataquets).
     * LDN servers removed as the service is now stopped.
     * Tidy up of remaining server data.
     * Change `comment` lines on Uncensored server data to more clearly
       be comments (not valid YAML)
     * Fix and improve descriptions of default values
     * getdnsapi.net DoT servers liston on port 443 now too
  * Fixes for parsing of quoted key values for `tls-ca-file`,
    `tls-curves-list` and `resolvconf`
  * Add Dockerfile into `contrib` - thanks to pataquets.
  * Strengthen version checking for LibIDN2 during the cmake step so
    LibIDN2 version 2.3.3 can be properly found (thanks jpbion).
  * Updated stubby.service file. Thanks Bruno Pagani
  * log level configurable in config file with log_level setting
    Command line setting (with -v or -l) overrules the config file
    setting

Signed-off-by: Aquila Cooper <aquila@cpr.is>