I'm not trying to be disrespectful friend, just you didn't mention whether it was running or functional afterward, nor an actual complete error line so hard to start troubleshooting. :)
Finding out if it starts properly from the webconfigurator after full up compared to at startup can potentially be a valid troubleshooting step that would lead to the cause.
edit:
Just built fresh 2.4.4_release-p3 vm and installed full squid package. As far as I can tell, every single edit to the squid configs generates a similar line in the logs. Restarting the machine also puts one in the log every single time. Tested the blocking function with the clam functions and with another vm successfully blocked the eicar test file...
While I cannot confirm or deny that the line is or is not an error, I think I can confirm that it existed before the 2.4.5 development freeze and that it has zero impact on functionality and probably not a blocker.
edit#2:
To clarify OP and my ???? in response the actual log line from normal config edits:
php-fpm 766 /pkg_edit.php: [squid] - squid_resync function call pr: bp: rpc:no
and
php-fpm 767 /pkg_edit.php: [squid] - squid_resync function call pr: bp: rpc:no
Actual log line from normal bootup:
php-fpm 339 /rc.start_packages: [squid] - squid_resync function call pr: bp: rpc:no