mydumper: update br to apply auto retry s3 read error (#533)

go.mod1

@@ -21,7 +21,7 @@ require (
 	github.com/google/uuid v1.1.1
 	github.com/joho/sqltocsv v0.0.0-20190824231449-5650f27fd5b6
 	github.com/pierrec/lz4 v2.6.0+incompatible // indirect
-	github.com/pingcap/br v4.0.0-beta.2.0.20201211063051-da9f975f3537+incompatible
+	github.com/pingcap/br v5.0.0-rc.0.20201223100334-c344d1edf20c+incompatible
 	github.com/pingcap/check v0.0.0-20200212061837-5e12011dc712
 	github.com/pingcap/errors v0.11.5-0.20201029093017-5a7df2af2ac7
 	github.com/pingcap/failpoint v0.0.0-20200702092429-9f69995143ce

go.sum1

@@ -779,8 +779,8 @@ github.com/pingcap-incubator/tidb-dashboard v0.0.0-20201022065613-94d8dc38a204/g
 github.com/pingcap/badger v1.5.1-0.20200908111422-2e78ee155d19 h1:IXpGy7y9HyoShAFmzW2OPF0xCA5EOoSTyZHwsgYk9Ro=
 github.com/pingcap/badger v1.5.1-0.20200908111422-2e78ee155d19/go.mod h1:LyrqUOHZrUDf9oGi1yoz1+qw9ckSIhQb5eMa1acOLNQ=
 github.com/pingcap/br v4.0.0-beta.2.0.20201014031603-5676c8fdad1a+incompatible/go.mod h1:ymVmo50lQydxib0tmK5hHk4oteB7hZ0IMCArunwy3UQ=
-github.com/pingcap/br v4.0.0-beta.2.0.20201211063051-da9f975f3537+incompatible h1:yopiXWTAiHNh7Ge/R+hltW91tUS7hpqjI78CZBkqspw=
-github.com/pingcap/br v4.0.0-beta.2.0.20201211063051-da9f975f3537+incompatible/go.mod h1:ymVmo50lQydxib0tmK5hHk4oteB7hZ0IMCArunwy3UQ=
+github.com/pingcap/br v5.0.0-rc.0.20201223100334-c344d1edf20c+incompatible h1:zWwhyjsFqG5VS910FTvw9F3y0Y7ghJXFfRCc91yv8u4=
+github.com/pingcap/br v5.0.0-rc.0.20201223100334-c344d1edf20c+incompatible/go.mod h1:ymVmo50lQydxib0tmK5hHk4oteB7hZ0IMCArunwy3UQ=
 github.com/pingcap/check v0.0.0-20190102082844-67f458068fc8/go.mod h1:B1+S9LNcuMyLH/4HMTViQOJevkGiik3wW2AN9zb2fNQ=
 github.com/pingcap/check v0.0.0-20191107115940-caf2b9e6ccf4/go.mod h1:PYMCGwN0JHjoqGr3HrZoD+b8Tgx8bKnArhSq8YVzUMc=
 github.com/pingcap/check v0.0.0-20191216031241-8a5a85928f12/go.mod h1:PYMCGwN0JHjoqGr3HrZoD+b8Tgx8bKnArhSq8YVzUMc=