Bump github.com/pkg/errors from 0.9.0 to 0.9.1

Bumps [github.com/pkg/errors](https://github.com/pkg/errors) from 0.9.0 to 0.9.1.
- [Release notes](https://github.com/pkg/errors/releases)
- [Commits](pkg/errors@v0.9.0...v0.9.1)

Signed-off-by: dependabot-preview[bot] <support@dependabot.com>

go.mod

@@ -9,7 +9,7 @@ require (
 	github.com/fsnotify/fsnotify v1.4.7 // indirect
 	github.com/hpcloud/tail v1.0.0
 	github.com/koding/multiconfig v0.0.0-20171124222453-69c27309b2d7
-	github.com/pkg/errors v0.9.0
+	github.com/pkg/errors v0.9.1
 	github.com/sirupsen/logrus v1.4.2
 	github.com/stretchr/testify v1.4.0
 	gopkg.in/fsnotify.v1 v1.4.7 // indirect

go.sum

@@ -19,6 +19,8 @@ github.com/pkg/errors v0.8.1 h1:iURUrRGxPUNPdy5/HRSm+Yj6okJ6UtLINN0Q9M4+h3I=
 github.com/pkg/errors v0.8.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pkg/errors v0.9.0 h1:J8lpUdobwIeCI7OiSxHqEwJUKvJwicL5+3v1oe2Yb4k=
 github.com/pkg/errors v0.9.0/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
+github.com/pkg/errors v0.9.1 h1:FEBLx1zS214owpjy7qsBeixbURkuhQAwrK5UwLGTwt4=
+github.com/pkg/errors v0.9.1/go.mod h1:bwawxfHBFNV+L2hUp1rHADufV3IMtnDRdf1r5NINEl0=
 github.com/pmezard/go-difflib v1.0.0 h1:4DBwDE0NGyQoBHbLQYPwSUPoCMWR5BEzIk/f1lZbAQM=
 github.com/pmezard/go-difflib v1.0.0/go.mod h1:iKH77koFhYxTK1pcRnkKkqfTogsbg7gZNVY4sRDYZ/4=
 github.com/sirupsen/logrus v1.4.2 h1:SPIRibHv4MatM3XXNO2BJeFLZwZ2LvZgfQ5+UNI2im4=