Bump gopkg.in/yaml.v2 from 2.2.7 to 2.2.8 (#3135)

Bumps [gopkg.in/yaml.v2](https://github.com/go-yaml/yaml) from 2.2.7 to 2.2.8.
- [Release notes](https://github.com/go-yaml/yaml/releases)
- [Commits](go-yaml/yaml@v2.2.7...v2.2.8)

---
updated-dependencies:
- dependency-name: gopkg.in/yaml.v2
  dependency-type: direct:production
...

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

Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

go.mod

@@ -38,7 +38,7 @@ require (
 	google.golang.org/grpc v1.27.0
 	gopkg.in/natefinch/lumberjack.v2 v2.0.0
 	gopkg.in/stretchr/testify.v1 v1.2.2 // indirect
-	gopkg.in/yaml.v2 v2.2.7
+	gopkg.in/yaml.v2 v2.2.8
 	k8s.io/api v0.0.0-20191004102349-159aefb8556b
 	k8s.io/apimachinery v0.17.0 // indirect
 	sqlflow.org/goalisa v0.0.0-20200618020317-68d3aad1344c

go.sum

@@ -501,8 +501,8 @@ gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWD
 gopkg.in/yaml.v2 v2.2.1/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.2/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.2.4/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
-gopkg.in/yaml.v2 v2.2.7 h1:VUgggvou5XRW9mHwD/yXxIYSMtY0zoKQf/v226p2nyo=
-gopkg.in/yaml.v2 v2.2.7/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.2.8 h1:obN1ZagJSUGI0Ek/LBmuj4SNLPfIny3KsKFopxRdj10=
+gopkg.in/yaml.v2 v2.2.8/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 honnef.co/go/tools v0.0.0-20180728063816-88497007e858/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
 honnef.co/go/tools v0.0.0-20190102054323-c2f93a96b099/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=
 honnef.co/go/tools v0.0.0-20190523083050-ea95bdfd59fc/go.mod h1:rf3lG4BRIbNafJWhAfAdb/ePZxsR/4RtNHQocxwk9r4=