chore(deps): bump github.com/sigstore/gitsign

Bumps [github.com/sigstore/gitsign](https://github.com/sigstore/gitsign) from 0.10.3-0.20241016191048-aa71ea860646 to 0.11.0.
- [Release notes](https://github.com/sigstore/gitsign/releases)
- [Changelog](https://github.com/sigstore/gitsign/blob/main/.goreleaser.yaml)
- [Commits](https://github.com/sigstore/gitsign/commits/v0.11.0)

---
updated-dependencies:
- dependency-name: github.com/sigstore/gitsign
  dependency-type: indirect
...

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

go.mod

@@ -1,6 +1,7 @@
 module github.com/gittuf/github-app
 
 go 1.22.8
+toolchain go1.23.3
 
 require (
 	cloud.google.com/go/kms v1.20.1
@@ -24,7 +25,7 @@ require (
 	cloud.google.com/go/compute/metadata v0.5.2 // indirect
 	cloud.google.com/go/iam v1.2.1 // indirect
 	cloud.google.com/go/longrunning v0.6.1 // indirect
-	dario.cat/mergo v1.0.0 // indirect
+	dario.cat/mergo v1.0.1 // indirect
 	github.com/Microsoft/go-winio v0.6.2 // indirect
 	github.com/ProtonMail/go-crypto v1.0.0 // indirect
 	github.com/asaskevich/govalidator v0.0.0-20230301143203-a9d515a09cc2 // indirect
@@ -103,6 +104,8 @@ require (
 	github.com/pelletier/go-toml/v2 v2.2.2 // indirect
 	github.com/pjbgf/sha1cd v0.3.0 // indirect
 	github.com/pkg/errors v0.9.1 // indirect
+	github.com/prometheus/client_golang v1.20.4 // indirect
+	github.com/prometheus/common v0.60.0 // indirect
 	github.com/sagikazarmark/locafero v0.6.0 // indirect
 	github.com/sagikazarmark/slog-shim v0.1.0 // indirect
 	github.com/sassoftware/relic v7.2.1+incompatible // indirect
@@ -111,18 +114,22 @@ require (
 	github.com/sergi/go-diff v1.3.2-0.20230802210424-5b0b94c5c0d3 // indirect
 	github.com/shibumi/go-pathspec v1.3.0 // indirect
 	github.com/sigstore/cosign/v2 v2.4.1 // indirect
-	github.com/sigstore/gitsign v0.10.3-0.20241016191048-aa71ea860646 // indirect
+	github.com/sigstore/gitsign v0.11.0 // indirect
 	github.com/sigstore/protobuf-specs v0.3.2 // indirect
 	github.com/sigstore/rekor v1.3.6 // indirect
 	github.com/sigstore/sigstore v1.8.10 // indirect
 	github.com/sigstore/sigstore-go v0.6.2 // indirect
+	github.com/sigstore/sigstore/pkg/signature/kms/aws v1.8.9 // indirect
+	github.com/sigstore/sigstore/pkg/signature/kms/azure v1.8.9 // indirect
+	github.com/sigstore/sigstore/pkg/signature/kms/gcp v1.8.9 // indirect
+	github.com/sigstore/sigstore/pkg/signature/kms/hashivault v1.8.9 // indirect
 	github.com/sigstore/timestamp-authority v1.2.2 // indirect
 	github.com/sirupsen/logrus v1.9.3 // indirect
 	github.com/skeema/knownhosts v1.2.2 // indirect
 	github.com/skratchdot/open-golang v0.0.0-20200116055534-eef842397966 // indirect
 	github.com/sourcegraph/conc v0.3.0 // indirect
 	github.com/spf13/afero v1.11.0 // indirect
-	github.com/spf13/cast v1.6.0 // indirect
+	github.com/spf13/cast v1.7.0 // indirect
 	github.com/spf13/cobra v1.8.1 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
 	github.com/spf13/viper v1.19.0 // indirect
@@ -136,15 +143,15 @@ require (
 	github.com/xanzy/ssh-agent v0.3.3 // indirect
 	go.mongodb.org/mongo-driver v1.15.1 // indirect
 	go.opencensus.io v0.24.0 // indirect
-	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.54.0 // indirect
-	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.54.0 // indirect
-	go.opentelemetry.io/otel v1.29.0 // indirect
-	go.opentelemetry.io/otel/metric v1.29.0 // indirect
-	go.opentelemetry.io/otel/trace v1.29.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/google.golang.org/grpc/otelgrpc v0.55.0 // indirect
+	go.opentelemetry.io/contrib/instrumentation/net/http/otelhttp v0.55.0 // indirect
+	go.opentelemetry.io/otel v1.30.0 // indirect
+	go.opentelemetry.io/otel/metric v1.30.0 // indirect
+	go.opentelemetry.io/otel/trace v1.30.0 // indirect
 	go.uber.org/multierr v1.11.0 // indirect
 	go.uber.org/zap v1.27.0 // indirect
-	golang.org/x/exp v0.0.0-20240613232115-7f521ea00fb8 // indirect
-	golang.org/x/mod v0.20.0 // indirect
+	golang.org/x/exp v0.0.0-20240909161429-701f63a606c0 // indirect
+	golang.org/x/mod v0.21.0 // indirect
 	golang.org/x/net v0.30.0 // indirect
 	golang.org/x/oauth2 v0.23.0 // indirect
 	golang.org/x/sync v0.8.0 // indirect