Bump github.com/google/go-cmp from 0.5.9 to 0.6.0

Bumps [github.com/google/go-cmp](https://github.com/google/go-cmp) from 0.5.9 to 0.6.0.
- [Release notes](https://github.com/google/go-cmp/releases)
- [Commits](google/go-cmp@v0.5.9...v0.6.0)

---
updated-dependencies:
- dependency-name: github.com/google/go-cmp
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

go.mod

@@ -9,7 +9,7 @@ require (
 	github.com/go-sql-driver/mysql v1.7.1
 	github.com/golang/glog v1.1.2
 	github.com/google/certificate-transparency-go v1.1.6
-	github.com/google/go-cmp v0.5.9
+	github.com/google/go-cmp v0.6.0
 	github.com/google/trillian v1.5.2
 	github.com/google/uuid v1.3.1
 	github.com/hashicorp/go-retryablehttp v0.7.4

go.sum

@@ -382,8 +382,8 @@ github.com/google/go-cmp v0.5.3/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/
 github.com/google/go-cmp v0.5.4/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.5/go.mod h1:v8dTdLbMG2kIc/vJvl+f65V22dbkXbowE6jgT/gNBxE=
 github.com/google/go-cmp v0.5.8/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
-github.com/google/go-cmp v0.5.9 h1:O2Tfq5qg4qc4AmwVlvv0oLiVAGB7enBSJ2x2DqQFi38=
-github.com/google/go-cmp v0.5.9/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
+github.com/google/go-cmp v0.6.0 h1:ofyhxvXcZhMsU5ulbFiLKl/XBFqE1GSq7atu8tAmTRI=
+github.com/google/go-cmp v0.6.0/go.mod h1:17dUlkBOakJ0+DkrSSNjCkIjxS6bF9zb3elmeNGIjoY=
 github.com/google/go-containerregistry v0.16.1 h1:rUEt426sR6nyrL3gt+18ibRcvYpKYdpsa5ZW7MA08dQ=
 github.com/google/go-containerregistry v0.16.1/go.mod h1:u0qB2l7mvtWVR5kNcbFIhFY1hLbf8eeGapA+vbFDCtQ=
 github.com/google/go-querystring v1.1.0 h1:AnCroh3fv4ZBgVIf1Iwtovgjaw/GiKJo8M8yD/fhyJ8=