go.mod: fix incorrect package dependency when etcd clientv3 used as libary.

go.mod

@@ -0,0 +1,63 @@
+module go.etcd.io/etcd
+
+go 1.12
+
+require (
+	github.com/beorn7/perks v1.0.1 // indirect
+	github.com/bgentry/speakeasy v0.1.0
+	github.com/coreos/bbolt v1.3.3
+	github.com/coreos/etcd v3.3.22+incompatible
+	github.com/coreos/go-semver v0.2.0
+	github.com/coreos/go-systemd v0.0.0-20190620071333-e64a0ec8b42a
+	github.com/coreos/pkg v0.0.0-20180108230652-97fdf19511ea
+	github.com/cpuguy83/go-md2man v0.0.0-20170603125239-23709d084719 // indirect
+	github.com/dgrijalva/jwt-go v3.0.0+incompatible
+	github.com/dustin/go-humanize v1.0.0
+	github.com/fatih/color v1.9.0 // indirect
+	github.com/gogo/protobuf v1.2.1
+	github.com/golang/groupcache v0.0.0-20190702054246-869f871628b6
+	github.com/golang/protobuf v1.4.2
+	github.com/google/btree v1.0.0
+	github.com/google/uuid v1.0.0
+	github.com/gorilla/websocket v0.0.0-20170926233335-4201258b820c // indirect
+	github.com/grpc-ecosystem/go-grpc-middleware v1.0.0
+	github.com/grpc-ecosystem/go-grpc-prometheus v0.0.0-20170826090648-0dafe0d496ea
+	github.com/grpc-ecosystem/grpc-gateway v1.3.1
+	github.com/inconshreveable/mousetrap v1.0.0 // indirect
+	github.com/jonboulle/clockwork v0.1.0
+	github.com/json-iterator/go v1.1.7
+	github.com/kr/pty v1.1.1
+	github.com/mattn/go-colorable v0.1.6 // indirect
+	github.com/mattn/go-runewidth v0.0.2 // indirect
+	github.com/matttproud/golang_protobuf_extensions v0.0.0-20181231171920-c182affec369 // indirect
+	github.com/modern-go/concurrent v0.0.0-20180306012644-bacd9c7ef1dd // indirect
+	github.com/modern-go/reflect2 v1.0.1
+	github.com/olekukonko/tablewriter v0.0.0-20170122224234-a0225b3f23b5
+	github.com/onsi/ginkgo v1.13.0 // indirect
+	github.com/pkg/errors v0.9.1 // indirect
+	github.com/prometheus/client_golang v0.0.0-20171005112915-5cec1d0429b0
+	github.com/prometheus/client_model v0.0.0-20170216185247-6f3806018612
+	github.com/prometheus/common v0.0.0-20171104095907-e3fb1a1acd76 // indirect
+	github.com/prometheus/procfs v0.0.0-20171017214025-a6e9df898b13 // indirect
+	github.com/russross/blackfriday v0.0.0-20170728175326-4048872b16cc // indirect
+	github.com/sirupsen/logrus v1.0.3 // indirect
+	github.com/soheilhy/cmux v0.1.4
+	github.com/spf13/cobra v0.0.0-20151124153217-1c44ec8d3f15
+	github.com/spf13/pflag v1.0.0
+	github.com/tmc/grpc-websocket-proxy v0.0.0-20170815181823-89b8d40f7ca8
+	github.com/urfave/cli v1.18.0
+	github.com/xiang90/probing v0.0.0-20160813154853-07dd2e8dfe18
+	go.etcd.io/bbolt v1.3.5 // indirect
+	go.uber.org/multierr v1.5.0 // indirect
+	go.uber.org/zap v1.10.0
+	golang.org/x/crypto v0.0.0-20190510104115-cbcb75029529
+	golang.org/x/net v0.0.0-20200520004742-59133d7f0dd7
+	golang.org/x/time v0.0.0-20170420181420-c06e80d9300e
+	google.golang.org/genproto v0.0.0-20180817151627-c66870c02cf8
+	google.golang.org/grpc v1.23.0
+	gopkg.in/airbrake/gobrake.v2 v2.0.9 // indirect
+	gopkg.in/cheggaaa/pb.v1 v1.0.2
+	gopkg.in/gemnasium/logrus-airbrake-hook.v2 v2.1.2 // indirect
+	gopkg.in/yaml.v2 v2.3.0
+	sigs.k8s.io/yaml v1.1.0
+)