Merge in GO/dnsproxy from depr-more-util to master

Squashed commit of the following:

commit 70f156d2742cfc4adc6813b04d40f37370ec9676
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Tue Apr 18 17:31:10 2023 +0300

    proxy: rm func

commit 7708f79024f46179d2414c38db781330453c0c74
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Tue Apr 18 17:28:54 2023 +0300

    all: depr more proxyutil funcs