[Inference API] Fix output stream ordering in InferenceActionProxy (#124225)

Author: timgrein

docs/changelog/124225.yaml

@@ -0,0 +1,5 @@
+pr: 124225
+summary: "[Inference API] Fix output stream ordering in `InferenceActionProxy`"
+area: Machine Learning
+type: bug
+issues: []

x-pack/plugin/core/src/main/java/org/elasticsearch/xpack/core/inference/action/InferenceActionProxy.java

@@ -105,8 +105,8 @@ public ActionRequestValidationException validate() {
  @Override
  public void writeTo(StreamOutput out) throws IOException {
  super.writeTo(out);
- out.writeString(inferenceEntityId);
  taskType.writeTo(out);
+ out.writeString(inferenceEntityId);
  out.writeBytesReference(content);
  XContentHelper.writeTo(out, contentType);
  out.writeTimeValue(timeout);