Run Buildkite CI on pull requests (#2331)

Author: pquentin

.buildkite/pull-requests.json

@@ -0,0 +1,9 @@
+{
+  "jobs": [
+    {
+      "enabled": true,
+      "pipeline_slug": "elasticsearch-py",
+      "allow_org_users": true
+    }
+  ]
+}

catalog-info.yaml

@@ -8,6 +8,8 @@ spec:
   type: library
   owner: group:clients-team
   lifecycle: production
+  dependsOn:
+    - "resource:elasticsearch-py"
 
 ---
 # yaml-language-server: $schema=https://gist.githubusercontent.com/elasticmachine/988b80dae436cafea07d9a4a460a011d/raw/e57ee3bed7a6f73077a3f55a38e76e40ec87a7cf/rre.schema.json
@@ -33,9 +35,6 @@ spec:
           access_level: MANAGE_BUILD_AND_READ
         everyone:
           access_level: READ_ONLY
-      provider_settings:
-        build_pull_requests: false
-        build_branches: false
       cancel_intermediate_builds: true
       cancel_intermediate_builds_branch_filter: '!main'
       schedules: