Bump gopkg.in/yaml.v2 from 2.3.0 to 2.4.0

Bumps [gopkg.in/yaml.v2](https://github.com/go-yaml/yaml) from 2.3.0 to 2.4.0.
- [Release notes](https://github.com/go-yaml/yaml/releases)
- [Commits](go-yaml/yaml@v2.3.0...v2.4.0)

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

go.mod

@@ -6,5 +6,5 @@ require (
 	github.com/onsi/gomega v1.10.1
 	github.com/paketo-buildpacks/packit v0.0.16
 	github.com/sclevine/spec v1.4.0
-	gopkg.in/yaml.v2 v2.3.0
+	gopkg.in/yaml.v2 v2.4.0 // indirect
 )

go.sum

@@ -85,3 +85,5 @@ gopkg.in/tomb.v1 v1.0.0-20141024135613-dd632973f1e7/go.mod h1:dt/ZhP58zS4L8KSrWD
 gopkg.in/yaml.v2 v2.2.4/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
 gopkg.in/yaml.v2 v2.3.0 h1:clyUAQHOM3G0M3f5vQj7LuJrETvjVot3Z5el9nffUtU=
 gopkg.in/yaml.v2 v2.3.0/go.mod h1:hI93XBmqTisBFMUTm0b8Fm+jr3Dg1NNxqwp+5A1VGuI=
+gopkg.in/yaml.v2 v2.4.0 h1:D8xgwECY7CYvx+Y2n4sBz93Jn9JRvxdiyyo8CTfuKaY=
+gopkg.in/yaml.v2 v2.4.0/go.mod h1:RDklbk79AGWmwhnvt/jBztapEOGDOx6ZbXqjP6csGnQ=