Merge in DNS/dnsproxy from 4503-upstream-conf to master

Squashed commit of the following:

commit abf53fe685fe04a851a1a74d0811d4f34466d1dc
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Fri May 13 15:51:58 2022 +0200

    proxy: imp code

commit e00ac4e33219132424d50b88f9f90f77607c5e1a
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Fri May 13 15:48:33 2022 +0200

    proxy: bench

commit 899aa7f5551b167f4f831809505e178603a68dd1
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Fri May 13 10:32:28 2022 +0200

    proxy: imp code

commit 156efa8c41502e9d4c31ea94877c4349c13f0735
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Wed May 11 14:10:36 2022 +0200

    proxy: imp code

commit 92fa2820487bd273e9a457ae62f83c25ed7c71c2
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Wed May 11 14:08:01 2022 +0200

    proxy: upper level check

commit 841d05246f41f7efa5ca3717c1901c0f848633da
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Wed May 11 11:53:26 2022 +0200

    proxy: imp code

commit 6725791a
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Fri May 6 16:51:34 2022 +0200

    proxy: wildcard exclusion

commit 35d69b4f
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Fri May 6 15:12:48 2022 +0200

    proxy: wildcard exclusion

commit 53cb4295
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Fri Apr 29 12:59:45 2022 +0200

    proxy: imp code

commit f1328a96
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Thu Apr 28 20:16:34 2022 +0200

    proxy: imp code

commit 79c0ef63
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Thu Apr 28 17:14:22 2022 +0200

    proxy: imp code

commit 70622f4d
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Thu Apr 28 17:09:01 2022 +0200

    all: docs

commit 1332e459
Author: Dimitry Kolyshev <dkolyshev@adguard.com>
Date:   Thu Apr 28 16:52:03 2022 +0200

    proxy: upstream config