update bazel-go-ethereum, delete unused deps (#3580)

WORKSPACE

@@ -194,7 +194,7 @@ protobuf_deps()
 
 go_repository(
     name = "com_github_ethereum_go_ethereum",
-    commit = "1c80f374f8d07774091c0574154bbef5b261d09d",
+    commit = "e72457320e5ab146ea573d01041a1b80b87e1489",
     importpath = "github.com/ethereum/go-ethereum",
     # Note: go-ethereum is not bazel-friendly with regards to cgo. We have a
     # a fork that has resolved these issues by disabling HID/USB support and
@@ -356,12 +356,6 @@ go_repository(
     importpath = "github.com/mattn/go-colorable",
 )
 
-go_repository(
-    name = "com_github_whyrusleeping_mdns",
-    commit = "ef14215e6b30606f4ce84174ed7a644a05cb1af3",
-    importpath = "github.com/whyrusleeping/mdns",
-)
-
 go_repository(
     name = "com_github_btcsuite_btcd",
     commit = "306aecffea325e97f513b3ff0cf7895a5310651d",
@@ -447,12 +441,6 @@ go_repository(
     importpath = "github.com/libp2p/go-libp2p-transport-upgrader",
 )
 
-go_repository(
-    name = "com_github_libp2p_go_testutil",
-    commit = "9a5d4c55819de9fd3e07181003d1e722621f6b84",  # v0.1.0
-    importpath = "github.com/libp2p/go-testutil",
-)
-
 go_repository(
     name = "com_github_libp2p_go_maddr_filter",
     commit = "4d5679194bce9c87a81d3b9948a4b5edd5ddc094",  # v0.0.5
@@ -483,12 +471,6 @@ go_repository(
     importpath = "github.com/whyrusleeping/timecache",
 )
 
-go_repository(
-    name = "com_github_miekg_dns",
-    commit = "b13675009d59c97f3721247d9efa8914e1866a5b",  # v1.1.15
-    importpath = "github.com/miekg/dns",
-)
-
 go_repository(
     name = "com_github_opentracing_opentracing_go",
     commit = "659c90643e714681897ec2521c60567dd21da733",  # v1.1.0
@@ -603,12 +585,6 @@ go_repository(
     importpath = "github.com/libp2p/go-libp2p-blankhost",
 )
 
-go_repository(
-    name = "com_github_steakknife_hamming",
-    commit = "c99c65617cd3d686aea8365fe563d6542f01d940",
-    importpath = "github.com/steakknife/hamming",
-)
-
 go_repository(
     name = "io_opencensus_go",
     commit = "7bbec1755a8162b5923fc214a494773a701d506a",  # v0.22.0
@@ -955,12 +931,6 @@ go_repository(
     importpath = "github.com/golang/snappy",
 )
 
-go_repository(
-    name = "com_github_rjeczalik_notify",
-    commit = "69d839f37b13a8cb7a78366f7633a4071cb43be7",  # v0.9.2
-    importpath = "github.com/rjeczalik/notify",
-)
-
 go_repository(
     name = "com_github_edsrzf_mmap_go",
     commit = "188cc3b666ba704534fa4f96e9e61f21f1e1ba7c",  # v1.0.0
@@ -979,12 +949,6 @@ go_repository(
     importpath = "gopkg.in/natefinch/npipe.v2",
 )
 
-go_repository(
-    name = "org_golang_x_exp",
-    commit = "438050ddec5e7f808979ed57d041cebbc8e2d8a9",
-    importpath = "golang.org/x/exp",
-)
-
 go_repository(
     name = "com_github_prestonvanloon_go_recaptcha",
     commit = "0834cef6e8bd3a7ebdb3ac7def9440ee47d501a4",
@@ -1140,12 +1104,6 @@ load("@com_github_prysmaticlabs_go_ssz//:deps.bzl", "go_ssz_dependencies")
 
 go_ssz_dependencies()
 
-go_repository(
-    name = "com_github_burntsushi_toml",
-    commit = "3012a1dbe2e4bd1391d42b32f0577cb7bbc7f005",  # v0.3.1
-    importpath = "github.com/BurntSushi/toml",
-)
-
 go_repository(
     name = "org_golang_google_grpc",
     build_file_proto_mode = "disable",
@@ -1177,30 +1135,12 @@ go_repository(
     importpath = "golang.org/x/time",
 )
 
-go_repository(
-    name = "com_github_gregjones_httpcache",
-    commit = "901d90724c7919163f472a9812253fb26761123d",
-    importpath = "github.com/gregjones/httpcache",
-)
-
-go_repository(
-    name = "com_github_peterbourgon_diskv",
-    commit = "0be1b92a6df0e4f5cb0a5d15fb7f643d0ad93ce6",  # v3.0.0
-    importpath = "github.com/peterbourgon/diskv",
-)
-
 go_repository(
     name = "com_github_googleapis_gnostic",
     commit = "ab0dd09aa10e2952b28e12ecd35681b20463ebab",  # v0.3.1
     importpath = "github.com/googleapis/gnostic",
 )
 
-go_repository(
-    name = "com_github_google_btree",
-    commit = "4030bb1f1f0c35b30ca7009e9ebd06849dd45306",  # v1.0.0
-    importpath = "github.com/google/btree",
-)
-
 go_repository(
     name = "in_gopkg_inf_v0",
     commit = "d2d2541c53f18d2a059457998ce2876cc8e67cbf",  # v0.9.1