Kubelet floods error logs with "[Startup|Readiness|Liveness] probe already exists for container" after upgrading to EKS 1.35

## Summary

After upgrading EKS from Kubernetes 1.34 to 1.35 using Bottlerocket 1.54.0, the kubelet continuously prints error-level log messages about probes already existing for containers. This is a known upstream issue introduced during the migration to contextual logging in Kubernetes 1.35, where `Error`-level logs were incorrectly wrapped with verbosity methods (`.V()`). Since `go-logr/logr` ignores verbosity levels for `Error`-level logs, these messages are emitted unconditionally, flooding the node logs.

Upstream references:
- https://github.com/kubernetes/kubernetes/issues/135996
- https://github.com/kubernetes/kubernetes/issues/136027

**Image I'm using:**

Bottlerocket 1.54.0 on EKS with EKS 1.35.

**What I expected to happen:**

Kubelet should not continuously print error-level log messages for probe-already-exists conditions. These should either be informational (downgraded to a lower log level) or suppressed by verbosity settings.

**What actually happened:**

Kubelet floods the journal/logs with error-level messages like:

```
Feb 25 14:55:33 ip-10-x-x-x.eu-west-3.compute.internal kubelet[1960]: E0225 14:55:33.475528 1960 prober_manager.go:197] "Startup probe already exists for container" pod="kube-system/daemonset-abc123" containerName="agent"
Feb 25 14:55:54 ip-10-x-x-x.eu-west-3.compute.internal kubelet[1960]: E0225 14:55:54.473357 1960 prober_manager.go:197] "Startup probe already exists for container" pod="my-namespace/my-app-5dd9846ccd-fwjw4" containerName="main"
Feb 25 14:56:16 ip-10-x-x-x.eu-west-3.compute.internal kubelet[1960]: E0225 14:56:16.473035 1960 prober_manager.go:197] "Startup probe already exists for container" pod="my-namespace/my-other-app-74df4b8d6c-hv4k5" containerName="main"
Feb 25 14:56:20 ip-10-x-x-x.eu-west-3.compute.internal kubelet[1960]: E0225 14:56:20.473113 1960 prober_manager.go:209] "Readiness probe already exists for container" pod="kube-system/ebs-csi-node-t54vr" containerName="ebs-plugin"
Feb 25 14:56:35 ip-10-x-x-x.eu-west-3.compute.internal kubelet[1960]: E0225 14:56:35.472674 1960 prober_manager.go:197] "Startup probe already exists for container" pod="kube-system/daemonset-abc123" containerName="agent"
```

These messages repeat continuously for every pod that has startup, readiness, or liveness probes configured, making it difficult to spot real errors in the kubelet logs.

**How to reproduce the problem:**

1. Have an EKS cluster running Kubernetes 1.34 on Bottlerocket.
2. Upgrade the cluster to Kubernetes 1.35 using Bottlerocket 1.54.0.
3. Observe kubelet logs on any node — error messages about probes already existing will appear continuously.

**Additional context:**

The root cause is in `pkg/kubelet/prober/prober_manager.go` (lines 197, 209, 221) where `logger.V(8).Error(nil, ...)` is used. Since `go-logr/logr` ignores the `.V()` level on `Error()` calls, these are always printed at error level regardless of the configured verbosity. The upstream fix (tracked in kubernetes/kubernetes#136027) is to convert these to `logger.V(8).Info(...)` instead.

Until the upstream fix is included in a Kubernetes release and picked up by Bottlerocket, this issue causes significant log noise on all nodes running Kubernetes 1.35.