Bump github.com/gardener/gardener from 1.137.1 to 1.137.4

Bumps [github.com/gardener/gardener](https://github.com/gardener/gardener) from 1.137.1 to 1.137.4.
- [Release notes](https://github.com/gardener/gardener/releases)
- [Commits](gardener/gardener@v1.137.1...v1.137.4)

---
updated-dependencies:
- dependency-name: github.com/gardener/gardener
  dependency-version: 1.137.4
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

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

Author: dependabot[bot]

go.mod

@@ -4,7 +4,7 @@ go 1.25.6
 
 require (
 	github.com/ahmetb/gen-crd-api-reference-docs v0.3.0
-	github.com/gardener/gardener v1.137.1
+	github.com/gardener/gardener v1.137.4
 	github.com/gardener/gardener/pkg/apis v1.137.0
 	github.com/gardener/network-problem-detector v0.31.0
 	github.com/go-logr/logr v1.4.3

go.sum

@@ -158,8 +158,8 @@ github.com/gardener/cert-management v0.19.0 h1:BNumdw748Pg9798NzxHmmpKuXFRLHSPuv
 github.com/gardener/cert-management v0.19.0/go.mod h1:u5OKwiDyUdCuW9vhDV92ozCVkynXUBrYCMHr4rVNiCY=
 github.com/gardener/etcd-druid/api v0.35.1 h1:hkd+5iV4xb7glnlo8rCqeXFIy9KmXF958x4une4cs6E=
 github.com/gardener/etcd-druid/api v0.35.1/go.mod h1:RwZzKp8K415AS0zg8VoODjBxYepCAUYyLgXnZc1bmbo=
-github.com/gardener/gardener v1.137.1 h1:Rm5gDgKhLJq8gZL1EkBFF38UM5oHbnwbCr1HvD0g17s=
-github.com/gardener/gardener v1.137.1/go.mod h1:wu6Q9hz+1Iod1/c1P6Eees6MTfXm9sS5jgirjyWSPWQ=
+github.com/gardener/gardener v1.137.4 h1:X+vE1lN3qDL/CxirXzoAAhFPirofiSyYuRwoGIWlxCM=
+github.com/gardener/gardener v1.137.4/go.mod h1:wu6Q9hz+1Iod1/c1P6Eees6MTfXm9sS5jgirjyWSPWQ=
 github.com/gardener/gardener/pkg/apis v1.137.0 h1:YK7OFoJ6lY4s4+Uoh0VWr/eJVo94S5fgSiiQBc+3ojs=
 github.com/gardener/gardener/pkg/apis v1.137.0/go.mod h1:QUINW0KPDxMiYQ5bAmIKnsK3oWpseuqMrHnLrMEC5W4=
 github.com/gardener/machine-controller-manager v0.61.2 h1:kG8DgmOqqlljWqxa4x0ER4+L5zg1lxNd1dQXT9gKbvA=