Rate Limiting Pod Creation Delay Causes 500 Errors

### Description

When enabling rate limiting, the pod creation for the rate limiting service takes a bit of time, and all incoming requests fail with HTTP 500 errors.

### Environment

- Envoy Gateway version: 1.7.1
- Kubernetes version: 1.33
- Rate limiter backend: elasticache valkey 8
- Cloud provider / platform: EKS

### Steps to Reproduce

1. Deploy Envoy Gateway with rate limiting enabled
2. Send requests to a route that has a `RateLimitFilter` applied during the deployment.
3. Observe that requests return HTTP 500 until the pod is fully ready.

### Expected Behavior

Requests should not fail with 500 errors while the rate limiting pod is not yet created, envoy gateway should handle the traffic properly

### Actual Behavior

All requests return HTTP 500 before the rate limiting pod is created.

**NB: when scaling the pod down the traffic is still handled fine, so this is happening just during the initial deployment.**