build(deps): Bump actions/attest-build-provenance from 1.4.0 to 1.4.2

Bumps [actions/attest-build-provenance](https://github.com/actions/attest-build-provenance) from 1.4.0 to 1.4.2.
- [Release notes](https://github.com/actions/attest-build-provenance/releases)
- [Changelog](https://github.com/actions/attest-build-provenance/blob/main/RELEASE.md)
- [Commits](actions/attest-build-provenance@210c191...6149ea5)

---
updated-dependencies:
- dependency-name: actions/attest-build-provenance
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

.github/workflows/caddy.yaml

@@ -55,7 +55,7 @@ jobs:
             CADDY_HASH=sha256:51b5e778a16d77474c37f8d1d966e6863cdb1c7478396b04b806169fed0abac9
 
       - name: Attest
-        uses: actions/attest-build-provenance@210c1913531870065f03ce1f9440dd87bc0938cd # v1.4.0
+        uses: actions/attest-build-provenance@6149ea5740be74af77f260b9db67e633f6b0a9a1 # v1.4.2
         id: attest
         with:
           subject-name: ghcr.io/caddyserver/gateway