Bump github.com/sigstore/sigstore from 1.5.2 to 1.6.0

Bumps [github.com/sigstore/sigstore](https://github.com/sigstore/sigstore) from 1.5.2 to 1.6.0.
- [Release notes](https://github.com/sigstore/sigstore/releases)
- [Commits](sigstore/sigstore@v1.5.2...v1.6.0)

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

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

go.mod

@@ -18,7 +18,7 @@ require (
 	github.com/mitchellh/go-homedir v1.1.0
 	github.com/opencontainers/image-spec v1.1.0-rc2
 	github.com/pkg/errors v0.9.1
-	github.com/sigstore/sigstore v1.5.2
+	github.com/sigstore/sigstore v1.6.0
 	github.com/spiffe/go-spiffe/v2 v2.1.2
 	github.com/spiffe/spire-api-sdk v1.5.5
 	github.com/tektoncd/plumbing v0.0.0-20220817140952-3da8ce01aeeb
@@ -71,8 +71,8 @@ require (
 	cloud.google.com/go/kms v1.8.0 // indirect
 	github.com/Azure/go-autorest/autorest/to v0.4.0 // indirect
 	github.com/Azure/go-autorest/autorest/validation v0.3.1 // indirect
-	github.com/aws/aws-sdk-go-v2/service/kms v1.20.4 // indirect
-	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.14.3 // indirect
+	github.com/aws/aws-sdk-go-v2/service/kms v1.20.5 // indirect
+	github.com/aws/aws-sdk-go-v2/service/ssooidc v1.14.4 // indirect
 	github.com/cenkalti/backoff/v3 v3.2.2 // indirect
 	github.com/cloudflare/circl v1.1.0 // indirect
 	github.com/emicklei/go-restful/v3 v3.9.0 // indirect
@@ -99,7 +99,7 @@ require (
 	github.com/rogpeppe/go-internal v1.8.0 // indirect
 	github.com/ryanuber/go-glob v1.0.0 // indirect
 	github.com/skeema/knownhosts v1.1.0 // indirect
-	github.com/theupdateframework/go-tuf v0.5.2-0.20220930112810-3890c1e7ace4 // indirect
+	github.com/theupdateframework/go-tuf v0.5.2 // indirect
 	github.com/zeebo/errs v1.3.0 // indirect
 )
 
@@ -117,17 +117,17 @@ require (
 	github.com/Azure/go-autorest/logger v0.2.1 // indirect
 	github.com/Azure/go-autorest/tracing v0.6.0 // indirect
 	github.com/aws/aws-sdk-go-v2 v1.17.5 // indirect
-	github.com/aws/aws-sdk-go-v2/config v1.18.14 // indirect
-	github.com/aws/aws-sdk-go-v2/credentials v1.13.14 // indirect
+	github.com/aws/aws-sdk-go-v2/config v1.18.15 // indirect
+	github.com/aws/aws-sdk-go-v2/credentials v1.13.15 // indirect
 	github.com/aws/aws-sdk-go-v2/feature/ec2/imds v1.12.23 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/configsources v1.1.29 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/endpoints/v2 v2.4.23 // indirect
 	github.com/aws/aws-sdk-go-v2/internal/ini v1.3.30 // indirect
 	github.com/aws/aws-sdk-go-v2/service/ecr v1.17.18 // indirect
 	github.com/aws/aws-sdk-go-v2/service/ecrpublic v1.13.17 // indirect
 	github.com/aws/aws-sdk-go-v2/service/internal/presigned-url v1.9.23 // indirect
-	github.com/aws/aws-sdk-go-v2/service/sso v1.12.3 // indirect
-	github.com/aws/aws-sdk-go-v2/service/sts v1.18.4 // indirect
+	github.com/aws/aws-sdk-go-v2/service/sso v1.12.4 // indirect
+	github.com/aws/aws-sdk-go-v2/service/sts v1.18.5 // indirect
 	github.com/aws/smithy-go v1.13.5 // indirect
 	github.com/awslabs/amazon-ecr-credential-helper/ecr-login v0.0.0-20221004211355-a250ad2ca1e3 // indirect
 	github.com/beorn7/perks v1.0.1 // indirect
@@ -186,7 +186,7 @@ require (
 	github.com/shurcooL/graphql v0.0.0-20181231061246-d48a9a75455f // indirect
 	github.com/sirupsen/logrus v1.9.0 // indirect
 	github.com/spf13/pflag v1.0.5 // indirect
-	github.com/stretchr/testify v1.8.1
+	github.com/stretchr/testify v1.8.2
 	github.com/vbatts/tar-split v0.11.2 // indirect
 	go.uber.org/atomic v1.10.0 // indirect
 	go.uber.org/automaxprocs v1.4.0 // indirect