fix(doc): hpa api version (#1274)

Signed-off-by: Derek Wang <[email protected]>

docs/user-guide/reference/autoscaling.md

@@ -12,7 +12,7 @@ Numaflow is able to run with both `Horizontal Pod Autoscaling` and `Vertical Pod
 
 ### Numaflow Autoscaling
 
-Numaflow provides `0 - N` autoscaling capability out of the box, it's available for all the `UDF`, `Sink` and most of 
+Numaflow provides `0 - N` autoscaling capability out of the box, it's available for all the `UDF`, `Sink` and most of
 the [`Source`](../sources/overview.md) vertices (please check each source for more details).
 
 Numaflow autoscaling is enabled by default, there are some parameters can be tuned to achieve better results.
@@ -40,23 +40,23 @@ spec:
 
 - `disabled` - Whether to disable Numaflow autoscaling, defaults to `false`.
 - `min` - Minimum replicas, valid value could be an integer >= 0. Defaults to `0`, which means it could be scaled down to 0.
-- `max` - Maximum replicas, positive integer which should not be less than `min`, defaults to `50`. if `max` and `min` 
+- `max` - Maximum replicas, positive integer which should not be less than `min`, defaults to `50`. if `max` and `min`
   are the same, that will be the fixed replica number.
-- `lookbackSeconds` - How many seconds to lookback for vertex average processing rate (tps) and pending messages calculation, 
+- `lookbackSeconds` - How many seconds to lookback for vertex average processing rate (tps) and pending messages calculation,
   defaults to `120`. Rate and pending messages metrics are critical for autoscaling, you might need to tune this parameter
-  a bit to see better results. For example, your data source only have 1 minute data input in every 5 minutes, and you 
-  don't want the vertices to be scaled down to `0`. In this case, you need to increase `lookbackSeconds` to cover all the 
-  5 minutes, so that the calculated average rate and pending messages won't be `0` during the silent period, to prevent 
+  a bit to see better results. For example, your data source only have 1 minute data input in every 5 minutes, and you
+  don't want the vertices to be scaled down to `0`. In this case, you need to increase `lookbackSeconds` to cover all the
+  5 minutes, so that the calculated average rate and pending messages won't be `0` during the silent period, to prevent
   scaling down to 0 from happening.
-- `scaleUpCooldownSeconds` - After a scaling operation, how many seconds to wait for the same vertex, if the follow-up 
+- `scaleUpCooldownSeconds` - After a scaling operation, how many seconds to wait for the same vertex, if the follow-up
   operation is a scaling up, defaults to `90`. Please make sure that the time is greater that the pod to be `Running` and
   start processing, because the autoscaling algorithm will divide the TPS by the number of pods even if the pod is not `Running`.
 - `scaleDownCooldownSeconds` - After a scaling operation, how many seconds to wait for the same vertex, if the follow-up
   operation is a scaling down, defaults to `90`.
 - `zeroReplicaSleepSeconds` - How many seconds it will wait after scaling down to `0`, defaults to `120`.
   Numaflow autoscaler periodically scales up a vertex pod to "peek" the incoming data, this is the period of time to wait before peeking.
-- `targetProcessingSeconds` - It is used to tune the aggressiveness of autoscaling for source vertices, it measures how 
-  fast you want the vertex to process all the pending messages, defaults to `20`. It is only effective for the `Source` vertices which 
+- `targetProcessingSeconds` - It is used to tune the aggressiveness of autoscaling for source vertices, it measures how
+  fast you want the vertex to process all the pending messages, defaults to `20`. It is only effective for the `Source` vertices which
   support autoscaling, typically increasing the value leads to lower processing rate, thus less replicas.
 - `targetBufferAvailability` - Targeted buffer availability in percentage, defaults to `50`. It is only effective for `UDF`
   and `Sink` vertices, it determines how aggressive you want to do for autoscaling, increasing the value will bring more replicas.
@@ -90,7 +90,7 @@ Numaflow autoscaling does not apply to reduce vertices, and following source ver
 [Kubernetes HPA](https://kubernetes.io/docs/tasks/run-application/horizontal-pod-autoscale/) is supported in Numaflow for any type of Vertex. To use HPA, remember to point the `scaleTargetRef` to the vertex as below, and disable Numaflow autoscaling in your Pipeline spec.
 
 ```yaml
-apiVersion: autoscaling/v2beta1
+apiVersion: autoscaling/v2
 kind: HorizontalPodAutoscaler
 metadata:
   name: my-vertex-hpa