Pull request: all: upd quic-go

Merge in DNS/dnsproxy from upd-quic-go to master

Squashed commit of the following:

commit 70465e7
Author: Ainar Garipov <A.Garipov@AdGuard.COM>
Date:   Wed Jun 16 18:39:41 2021 +0300

    all: upd quic-go

go.mod

@@ -1,27 +1,24 @@
 module github.com/AdguardTeam/dnsproxy
 
-go 1.15
+go 1.16
 
 require (
 	github.com/AdguardTeam/golibs v0.4.4
 	github.com/ameshkov/dnscrypt/v2 v2.1.3
 	github.com/ameshkov/dnsstamps v1.0.3
 	github.com/beefsack/go-rate v0.0.0-20200827232406-6cde80facd47
 	github.com/go-test/deep v1.0.5
-	github.com/golang/protobuf v1.4.3 // indirect
 	github.com/jessevdk/go-flags v1.4.0
 	github.com/joomcode/errorx v1.0.3
 	github.com/kr/text v0.2.0 // indirect
-	github.com/lucas-clemente/quic-go v0.20.1
+	github.com/lucas-clemente/quic-go v0.21.1
 	github.com/miekg/dns v1.1.40
 	github.com/niemeyer/pretty v0.0.0-20200227124842-a10e7caefd8e // indirect
 	github.com/patrickmn/go-cache v2.1.0+incompatible
 	github.com/stretchr/testify v1.6.1
 	golang.org/x/crypto v0.0.0-20201208171446-5f87f3452ae9 // indirect
-	golang.org/x/net v0.0.0-20201209123823-ac852fbbde11
-	golang.org/x/sync v0.0.0-20200317015054-43a5402ce75a // indirect
+	golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4
 	golang.org/x/text v0.3.4 // indirect
-	google.golang.org/protobuf v1.25.0 // indirect
 	gopkg.in/check.v1 v1.0.0-20200227125254-8fa46927fb4f // indirect
 	gopkg.in/yaml.v3 v3.0.0-20200615113413-eeeca48fe776
 )