docs: fix broken relref to realtime page (#10255)

Hugo fails the gh-pages build with REF_NOT_FOUND because the relref
in model-configuration.md uses the 'docs/' prefix; refs are resolved
relative to content/, so the page lives at 'features/openai-realtime'
(as the other ref in the same file already uses).


Assisted-by: Claude Code:claude-fable-5

Signed-off-by: Ettore Di Giacinto <mudler@localai.io>
Co-authored-by: Ettore Di Giacinto <mudler@localai.io>

docs/content/advanced/model-configuration.md

@@ -429,7 +429,7 @@ name: my-model
 reasoning_effort: none   # none | minimal | low | medium | high
 ```
 
-For [realtime pipelines]({{%relref "docs/features/openai-realtime" %}}), set it on the pipeline so it applies to the pipeline's LLM without editing that model's own config:
+For [realtime pipelines]({{%relref "features/openai-realtime" %}}), set it on the pipeline so it applies to the pipeline's LLM without editing that model's own config:
 
 ```yaml
 name: gpt-realtime