Log Message:
www/squid4: update to 4.16

Changes in squid-4.16 (04 Jul 2021):

	- Regression Fix: --with-valgrind-debug build broken since 4.15
	- Bug 5129 pt1: remove Lock use from HttpRequestMethod
	- Bug 5128: Translation: Fix '% i' typo in es/ERR_FORWARDING_DENIED
	- Bug 4528: ICAP transactions quit on async DNS lookups