Update dependencies (#4569)

As dependabot has been failing for some time,
this PR manually updates all dependencies when possible.
Signed-off-by: Yong Tang <yong.tang.github@outlook.com>

go.mod

@@ -3,12 +3,12 @@ module github.com/coredns/coredns
 go 1.16
 
 require (
-	github.com/Azure/azure-sdk-for-go v40.6.0+incompatible
+	github.com/Azure/azure-sdk-for-go v53.1.0+incompatible
 	github.com/Azure/go-autorest/autorest v0.11.18
 	github.com/Azure/go-autorest/autorest/azure/auth v0.5.7
 	github.com/Azure/go-autorest/autorest/to v0.2.0 // indirect
 	github.com/DataDog/datadog-go v3.5.0+incompatible // indirect
-	github.com/aws/aws-sdk-go v1.37.10
+	github.com/aws/aws-sdk-go v1.38.16
 	github.com/coredns/caddy v1.1.0
 	github.com/dnstap/golang-dnstap v0.4.0
 	github.com/dustin/go-humanize v1.0.0 // indirect
@@ -16,21 +16,23 @@ require (
 	github.com/golang/protobuf v1.4.3
 	github.com/grpc-ecosystem/grpc-opentracing v0.0.0-20180507213350-8e809c8a8645
 	github.com/hashicorp/golang-lru v0.5.4 // indirect
-	github.com/imdario/mergo v0.3.9 // indirect
-	github.com/infobloxopen/go-trees v0.0.0-20190313150506-2af4e13f9062
+	github.com/imdario/mergo v0.3.12 // indirect
+	github.com/infobloxopen/go-trees v0.0.0-20200715205103-96a057b8dfb9
 	github.com/matttproud/golang_protobuf_extensions v1.0.1
-	github.com/miekg/dns v1.1.40
+	github.com/miekg/dns v1.1.41
 	github.com/opentracing/opentracing-go v1.2.0
 	github.com/openzipkin-contrib/zipkin-go-opentracing v0.4.5
 	github.com/openzipkin/zipkin-go v0.2.2
-	github.com/philhofer/fwd v1.0.0 // indirect
+	github.com/philhofer/fwd v1.1.1 // indirect
 	github.com/prometheus/client_golang v1.9.0
 	github.com/prometheus/client_model v0.2.0
 	github.com/prometheus/common v0.15.0
 	go.etcd.io/etcd v0.5.0-alpha.5.0.20200306183522-221f0cc107cb
-	go.uber.org/zap v1.14.1 // indirect
-	golang.org/x/crypto v0.0.0-20210220033148-5ea612d1eb83
-	golang.org/x/sys v0.0.0-20210225134936-a50acf3fe073
+	go.uber.org/multierr v1.6.0 // indirect
+	go.uber.org/zap v1.16.0 // indirect
+	golang.org/x/crypto v0.0.0-20210322153248-0c34fe9e7dc2
+	golang.org/x/net v0.0.0-20210405180319-a5a99cb37ef4 // indirect
+	golang.org/x/sys v0.0.0-20210403161142-5e06dd20ab57
 	google.golang.org/api v0.29.0
 	google.golang.org/grpc v1.29.1
 	gopkg.in/DataDog/dd-trace-go.v1 v1.28.0