added pre-commit to x-pack/agentbeat (elastic#40965)

Author: oakrizan

.buildkite/x-pack/pipeline.xpack.agentbeat.yml

@@ -3,7 +3,30 @@ env:
   GCP_HI_PERF_MACHINE_TYPE: "c2d-highcpu-16"
   IMAGE_UBUNTU_X86_64: "family/platform-ingest-beats-ubuntu-2204"
 
+  IMAGE_BEATS_WITH_HOOKS_LATEST: "docker.elastic.co/ci-agent-images/platform-ingest/buildkite-agent-beats-ci-with-hooks:latest"
+
 steps:
+  - group: "Check/Update"
+    key: "x-pack-agentbeat-check-update"
+
+    steps:
+      - label: "agentbeat: Run pre-commit"
+        command: "pre-commit run --all-files"
+        agents:
+          image: "${IMAGE_BEATS_WITH_HOOKS_LATEST}"
+          memory: "2Gi"
+          useCustomGlobalHooks: true
+        notify:
+          - github_commit_status:
+              context: "agentbeat: pre-commit"
+
+  - wait: ~
+    # with PRs, we want to run mandatory tests only if check/update step succeed
+    # for other cases, e.g. merge commits, we want to run mundatory test (and publish) independently of other tests
+    # this allows building DRA artifacts even if there is flakiness in check/update step
+    if: build.env("BUILDKITE_PULL_REQUEST") != "false"
+    depends_on: "x-pack-agentbeat-check-update"
+
   - group: "Agentbeat tests"
     key: "agentbeat-mandatory-tests"