build(deps): bump github.com/docker/docker in /testing (#5612)

Bumps [github.com/docker/docker](https://github.com/docker/docker) from 28.4.0+incompatible to 28.5.0+incompatible.
- [Release notes](https://github.com/docker/docker/releases)
- [Commits](moby/moby@v28.4.0...v28.5.0)

---
updated-dependencies:
- dependency-name: github.com/docker/docker
  dependency-version: 28.5.0+incompatible
  dependency-type: direct:production
  update-type: version-update:semver-minor
...

Signed-off-by: dependabot[bot] <[email protected]>
Co-authored-by: dependabot[bot] <49699333+dependabot[bot]@users.noreply.github.com>

Author: dependabot[bot]

testing/go.mod

@@ -9,7 +9,7 @@ replace (
 
 require (
 	github.com/Shopify/toxiproxy/v2 v2.12.0
-	github.com/docker/docker v28.4.0+incompatible
+	github.com/docker/docker v28.5.0+incompatible
 	github.com/elastic/elastic-agent-client/v7 v7.17.2
 	github.com/elastic/elastic-agent-libs v0.24.1
 	github.com/elastic/fleet-server/pkg/api v0.0.0-00010101000000-000000000000

testing/go.sum

@@ -37,8 +37,8 @@ github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f h1:lO4WD4F/r
 github.com/dgryski/go-rendezvous v0.0.0-20200823014737-9f7001d12a5f/go.mod h1:cuUVRXasLTGF7a8hSLbxyZXjz+1KgoB3wDUb6vlszIc=
 github.com/distribution/reference v0.6.0 h1:0IXCQ5g4/QMHHkarYzh5l+u8T3t73zM5QvfrDyIgxBk=
 github.com/distribution/reference v0.6.0/go.mod h1:BbU0aIcezP1/5jX/8MP0YiH4SdvB5Y4f/wlDRiLyi3E=
-github.com/docker/docker v28.4.0+incompatible h1:KVC7bz5zJY/4AZe/78BIvCnPsLaC9T/zh72xnlrTTOk=
-github.com/docker/docker v28.4.0+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
+github.com/docker/docker v28.5.0+incompatible h1:ZdSQoRUE9XxhFI/B8YLvhnEFMmYN9Pp8Egd2qcaFk1E=
+github.com/docker/docker v28.5.0+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
 github.com/docker/go-connections v0.6.0 h1:LlMG9azAe1TqfR7sO+NJttz1gy6KO7VJBh+pMmjSD94=
 github.com/docker/go-connections v0.6.0/go.mod h1:AahvXYshr6JgfUJGdDCs2b5EZG/vmaMAntpSFH5BFKE=
 github.com/docker/go-units v0.5.0 h1:69rxXcBk27SvSaaxTtLh/8llcHD8vYHT7WSdRZ/jvr4=