[jsonnet] removed deprecated policy.v1beta1 (grafana#9978)

**What this PR does / why we need it**:
in k8s version 1.25 some k8s APIs are deprecated, such as policy.v1beta1
which is moved to policy.v1

**Checklist**
- [ ] Reviewed the
[`CONTRIBUTING.md`](https://github.com/grafana/loki/blob/main/CONTRIBUTING.md)
guide (**required**)
- [ ] Documentation added
- [ ] Tests updated
- [x] `CHANGELOG.md` updated
- [ ] If the change is worth mentioning in the release notes, add
`add-to-release-notes` label
- [ ] Changes that require user attention or interaction to upgrade are
documented in `docs/sources/upgrading/_index.md`
- [ ] For Helm chart changes bump the Helm chart version in
`production/helm/loki/Chart.yaml` and update
`production/helm/loki/CHANGELOG.md` and
`production/helm/loki/README.md`. [Example
PR](grafana@d10549e)

---------

Signed-off-by: Vladyslav Diachenko <vlad.diachenko@grafana.com>

CHANGELOG.md

@@ -113,6 +113,7 @@
 * [9790](https://github.com/grafana/loki/pull/9790) **manohar-koukuntla**: Add TSDB equivalent of `use_boltdb_shipper` flag to be able to configure `tsdb_shipper` section.
 * [8855](https://github.com/grafana/loki/pull/8855) **JoaoBraveCoding**: Add gRPC port to loki compactor mixin
 * [8880](https://github.com/grafana/loki/pull/8880) **JoaoBraveCoding**: Normalize headless service name for query-frontend/scheduler
+* [9978](https://github.com/grafana/loki/pull/9978) ****vlad-diachenko****: replaced deprecated `policy.v1beta1` with `policy.v1`.
 
 ## 2.8.2 (2023-05-03)
 

docs/sources/upgrading/_index.md

@@ -93,6 +93,18 @@ If you have a use-case that relies on strict parsing where you expect the parser
 logfmt parser doesn't include standalone keys(keys without a value) in the resulting label set anymore.
 You can use `--keep-empty` flag to retain them.
 
+### Jsonnet
+
+##### Deprecated PodDisruptionBudget definition has been removed
+
+The `policy/v1beta1` API version of PodDisruptionBudget is no longer served as of Kubernetes v1.25.
+To support the latest versions of the Kubernetes, it was necessary to replace `policy/v1beta1` with the new definition `policy/v1` that is available since v1.21. 
+
+No impact is expected if you use Kubernetes v1.21 or newer.
+
+Please refer to [official migration guide](https://kubernetes.io/docs/reference/using-api/deprecation-guide/#poddisruptionbudget-v125) for more details.
+
+
 ## 2.8.0
 
 ### Loki

production/ksonnet/loki/common.libsonnet

@@ -48,7 +48,7 @@ local k = import 'ksonnet-util/kausal.libsonnet';
 
   // functions for k8s objects
   newLokiPdb(deploymentName, maxUnavailable=1)::
-    local podDisruptionBudget = $.policy.v1beta1.podDisruptionBudget;
+    local podDisruptionBudget = $.policy.v1.podDisruptionBudget;
     local pdbName = '%s-pdb' % deploymentName;
 
     podDisruptionBudget.new() +

production/ksonnet/loki/ingester.libsonnet

@@ -82,7 +82,7 @@ local k = import 'ksonnet-util/kausal.libsonnet';
     else
       k.util.serviceFor($.ingester_statefulset, $._config.service_ignored_labels),
 
-  local podDisruptionBudget = k.policy.v1beta1.podDisruptionBudget,
+  local podDisruptionBudget = k.policy.v1.podDisruptionBudget,
 
   ingester_pdb:
     podDisruptionBudget.new() +

production/ksonnet/loki/multi-zone.libsonnet

@@ -2,7 +2,7 @@
   local container = $.core.v1.container,
   local deployment = $.apps.v1.deployment,
   local statefulSet = $.apps.v1.statefulSet,
-  local podDisruptionBudget = $.policy.v1beta1.podDisruptionBudget,
+  local podDisruptionBudget = $.policy.v1.podDisruptionBudget,
   local volume = $.core.v1.volume,
   local roleBinding = $.rbac.v1.roleBinding,
   local role = $.rbac.v1.role,