Bump golang.org/x/mod from 0.12.0 to 0.13.0

Bumps [golang.org/x/mod](https://github.com/golang/mod) from 0.12.0 to 0.13.0.
- [Commits](golang/mod@v0.12.0...v0.13.0)

---
updated-dependencies:
- dependency-name: golang.org/x/mod
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

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

go.mod

@@ -6,7 +6,7 @@ require (
 	github.com/google/go-cmp v0.5.9
 	github.com/transparency-dev/formats v0.0.0-20230914071414-5732692f1e50
 	github.com/transparency-dev/merkle v0.0.2
-	golang.org/x/mod v0.12.0
+	golang.org/x/mod v0.13.0
 	golang.org/x/sync v0.3.0
 	k8s.io/klog/v2 v2.100.1
 )

go.sum

@@ -6,8 +6,8 @@ github.com/transparency-dev/formats v0.0.0-20230914071414-5732692f1e50 h1:FVMl+j
 github.com/transparency-dev/formats v0.0.0-20230914071414-5732692f1e50/go.mod h1:J2NdDb6IhKIvF6MwCvKikz9/QStRylEtS2mv+En+jBg=
 github.com/transparency-dev/merkle v0.0.2 h1:Q9nBoQcZcgPamMkGn7ghV8XiTZ/kRxn1yCG81+twTK4=
 github.com/transparency-dev/merkle v0.0.2/go.mod h1:pqSy+OXefQ1EDUVmAJ8MUhHB9TXGuzVAT58PqBoHz1A=
-golang.org/x/mod v0.12.0 h1:rmsUpXtvNzj340zd98LZ4KntptpfRHwpFOHG188oHXc=
-golang.org/x/mod v0.12.0/go.mod h1:iBbtSCu2XBx23ZKBPSOrRkjjQPZFPuis4dIYUhu/chs=
+golang.org/x/mod v0.13.0 h1:I/DsJXRlw/8l/0c24sM9yb0T4z9liZTduXvdAWYiysY=
+golang.org/x/mod v0.13.0/go.mod h1:hTbmBsO62+eylJbnUtE2MGJUyE7QWk4xUqPFrRgJ+7c=
 golang.org/x/sync v0.3.0 h1:ftCYgMx6zT/asHUrPw8BLLscYtGznsLAnjq5RH9P66E=
 golang.org/x/sync v0.3.0/go.mod h1:FU7BRWz2tNW+3quACPkgCx/L+uEAv1htQ0V83Z9Rj+Y=
 k8s.io/klog/v2 v2.100.1 h1:7WCHKK6K8fNhTqfBhISHQ97KrnJNFZMcQvKp7gP/tmg=