Bump github.com/go-sql-driver/mysql from 1.7.1 to 1.8.1

Bumps [github.com/go-sql-driver/mysql](https://github.com/go-sql-driver/mysql) from 1.7.1 to 1.8.1.
- [Release notes](https://github.com/go-sql-driver/mysql/releases)
- [Changelog](https://github.com/go-sql-driver/mysql/blob/master/CHANGELOG.md)
- [Commits](go-sql-driver/mysql@v1.7.1...v1.8.1)

---
updated-dependencies:
- dependency-name: github.com/go-sql-driver/mysql
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>

go.mod

@@ -10,7 +10,7 @@ require (
 	github.com/alecthomas/units v0.0.0-20190924025748-f65c72e2690d // indirect
 	github.com/emersion/go-imap v1.2.1
 	github.com/emersion/go-message v0.17.0
-	github.com/go-sql-driver/mysql v1.7.1
+	github.com/go-sql-driver/mysql v1.8.1
 	github.com/gophish/gomail v0.0.0-20200818021916-1f6d0dfd512e
 	github.com/gorilla/context v1.1.2
 	github.com/gorilla/csrf v1.7.2

go.sum

@@ -1,5 +1,7 @@
 bitbucket.org/liamstask/goose v0.0.0-20150115234039-8488cc47d90c h1:bkb2NMGo3/Du52wvYj9Whth5KZfMV6d3O0Vbr3nz/UE=
 bitbucket.org/liamstask/goose v0.0.0-20150115234039-8488cc47d90c/go.mod h1:hSVuE3qU7grINVSwrmzHfpg9k87ALBk+XaualNyUzI4=
+filippo.io/edwards25519 v1.1.0 h1:FNf4tywRC1HmFuKW5xopWpigGjJKiJSV0Cqo0cJWDaA=
+filippo.io/edwards25519 v1.1.0/go.mod h1:BxyFTGdWcka3PhytdK4V28tE5sGfRvvvRV7EaN4VDT4=
 github.com/NYTimes/gziphandler v1.1.1 h1:ZUDjpQae29j0ryrS0u/B8HZfJBtBQHjqw2rQ2cqUQ3I=
 github.com/NYTimes/gziphandler v1.1.1/go.mod h1:n/CVRwUEOgIxrgPvAQhUUr9oeUtvrhMomdKFjzJNB0c=
 github.com/PuerkitoBio/goquery v1.5.1/go.mod h1:GsLWisAFVj4WgDibEWF4pvYnkVQBpKBKeU+7zCJoLcc=
@@ -31,8 +33,8 @@ github.com/erikstmartin/go-testdb v0.0.0-20160219214506-8d10e4a1bae5/go.mod h1:a
 github.com/felixge/httpsnoop v1.0.1 h1:lvB5Jl89CsZtGIWuTcDM1E/vkVs49/Ml7JJe07l8SPQ=
 github.com/felixge/httpsnoop v1.0.1/go.mod h1:m8KPJKqk1gH5J9DgRY2ASl2lWCfGKXixSwevea8zH2U=
 github.com/go-sql-driver/mysql v1.5.0/go.mod h1:DCzpHaOWr8IXmIStZouvnhqoel9Qv2LBy8hT2VhHyBg=
-github.com/go-sql-driver/mysql v1.7.1 h1:lUIinVbN1DY0xBg0eMOzmmtGoHwWBbvnWubQUrtU8EI=
-github.com/go-sql-driver/mysql v1.7.1/go.mod h1:OXbVy3sEdcQ2Doequ6Z5BW6fXNQTmx+9S1MCJN5yJMI=
+github.com/go-sql-driver/mysql v1.8.1 h1:LedoTUt/eveggdHS9qUFC1EFSa8bU2+1pZjSRpvNJ1Y=
+github.com/go-sql-driver/mysql v1.8.1/go.mod h1:wEBSXgmK//2ZFJyE+qWnIsVGmvmEKlqwuVSjsCm7DZg=
 github.com/golang-sql/civil v0.0.0-20190719163853-cb61b32ac6fe h1:lXe2qZdvpiX5WZkZR4hgp4KJVfY3nMkvmwbVkpv1rVY=
 github.com/golang-sql/civil v0.0.0-20190719163853-cb61b32ac6fe/go.mod h1:8vg3r2VgvsThLBIFL93Qb5yWzgyZWhEmBwUJWevAkK0=
 github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=