feat(inference): add medgemma as compatible custom models (#5338)

Author: fpagny

pages/managed-inference/reference-content/supported-models.mdx

@@ -238,6 +238,7 @@ Several models have already been verified to work on Managed Inference custom mo
 <Accordion>
   ## Models verified for compatibility
   The following model compatibility has been verified:
+  * `google/medgemma-27b-it`
   * `HuggingFaceTB/SmolLM2-135M-Instruct`
   * `ibm-granite/granite-vision-3.2-2b`
   * `ibm-granite/granite-3.3-2b-instruct`