values.yaml example are missing encryptionKey

When using the example values the `encryptionKey` key under `n8n` is missing:

```
Pulled: ghcr.io/a5r0n/charts/n8n:0.3.0
Digest: sha256:5804cf928892b7996b64a21efea2365d854bb4893a209ed9a8adfb418b0b0e75
Error: INSTALLATION FAILED: execution error at (n8n/templates/configmap.yaml:6:53): encryptionKey is required to make sure u won't lose access to credentials
```