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

Bumps [github.com/docker/docker](https://github.com/docker/docker) from 26.1.4+incompatible to 26.1.5+incompatible.
- [Release notes](https://github.com/docker/docker/releases)
- [Commits](moby/moby@v26.1.4...v26.1.5)

---
updated-dependencies:
- dependency-name: github.com/docker/docker
  dependency-type: direct:production
...

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

Author: dependabot[bot]

testing/go.mod

@@ -9,7 +9,7 @@ replace (
 
 require (
 	github.com/Shopify/toxiproxy v2.1.4+incompatible
-	github.com/docker/docker v26.1.4+incompatible
+	github.com/docker/docker v26.1.5+incompatible
 	github.com/elastic/elastic-agent-client/v7 v7.15.0
 	github.com/elastic/fleet-server/pkg/api v0.0.0-00010101000000-000000000000
 	github.com/elastic/fleet-server/v7 v7.0.0-00010101000000-000000000000

testing/go.sum

@@ -29,8 +29,8 @@ github.com/davecgh/go-spew v1.1.1 h1:vj9j/u1bqnvCEfJOwUhtlOARqs3+rkHYY13jYWTU97c
 github.com/davecgh/go-spew v1.1.1/go.mod h1:J7Y8YcW2NihsgmVo/mv3lAwl/skON4iLHjSsI+c5H38=
 github.com/distribution/reference v0.5.0 h1:/FUIFXtfc/x2gpa5/VGfiGLuOIdYa1t65IKK2OFGvA0=
 github.com/distribution/reference v0.5.0/go.mod h1:BbU0aIcezP1/5jX/8MP0YiH4SdvB5Y4f/wlDRiLyi3E=
-github.com/docker/docker v26.1.4+incompatible h1:vuTpXDuoga+Z38m1OZHzl7NKisKWaWlhjQk7IDPSLsU=
-github.com/docker/docker v26.1.4+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
+github.com/docker/docker v26.1.5+incompatible h1:NEAxTwEjxV6VbBMBoGG3zPqbiJosIApZjxlbrG9q3/g=
+github.com/docker/docker v26.1.5+incompatible/go.mod h1:eEKB0N0r5NX/I1kEveEz05bcu8tLC/8azJZsviup8Sk=
 github.com/docker/go-connections v0.5.0 h1:USnMq7hx7gwdVZq1L49hLXaFtUdTADjXGp+uj1Br63c=
 github.com/docker/go-connections v0.5.0/go.mod h1:ov60Kzw0kKElRwhNs9UlUHAE/F9Fe6GLaXnqyDdmEXc=
 github.com/docker/go-units v0.5.0 h1:69rxXcBk27SvSaaxTtLh/8llcHD8vYHT7WSdRZ/jvr4=