The munkitools_launchd.pkg component package is still built with a restart required flag, as seen in component PackageInfo file:
<pkg-info format-version="2" install-location="/" postinstall-action="restart" identifier="com.googlecode.munki.launchd" version="6.6.0.4656" generator-version="InstallCmds-830.2 (22G810)" auth="root">
This is not an issue in the distribution package, but is a problem when the AutoPkg munkitools6 recipes breaks out the individual componet packages used for updating existing installs.
Fix in make_munki_mpkg.sh, change restart to norestart here:
https://github.com/munki/munki/blob/12d997569bd072e188d19cfb8e6a8320271e79e4/code/tools/make_munki_mpkg.sh#L627-rob