upgrade go-sql-driver/mysql to fix invalid connection error (#5748)

should fix #5736

vendor/github.com/go-sql-driver/mysql/AUTHORS

@@ -35,6 +35,7 @@ Hanno Braun <mail at hannobraun.com>
 Henri Yandell <flamefew at gmail.com>
 Hirotaka Yamamoto <ymmt2005 at gmail.com>
 ICHINOSE Shogo <shogo82148 at gmail.com>
+Ilia Cimpoes <ichimpoesh at gmail.com>
 INADA Naoki <songofacandy at gmail.com>
 Jacek Szwec <szwec.jacek at gmail.com>
 James Harr <james.harr at gmail.com>
@@ -72,6 +73,9 @@ Shuode Li <elemount at qq.com>
 Soroush Pour <me at soroushjp.com>
 Stan Putrya <root.vagner at gmail.com>
 Stanley Gunawan <gunawan.stanley at gmail.com>
+Steven Hartland <steven.hartland at multiplay.co.uk>
+Thomas Wodarek <wodarekwebpage at gmail.com>
+Tom Jenkinson <tom at tjenkinson.me>
 Xiangyu Hu <xiangyu.hu at outlook.com>
 Xiaobing Jiang <s7v7nislands at gmail.com>
 Xiuming Chen <cc at cxm.cc>
@@ -87,3 +91,4 @@ Keybase Inc.
 Percona LLC
 Pivotal Inc.
 Stripe Inc.
+Multiplay Ltd.