CI: Refactor/Reorder *.star files (#52384)

* Refactor test pipelines

* Move pr, main and release starlark files under scripts/drone/event

* Move cron.star to scripts/drone/events

* Further unused code removal

* Introducing build.star

* Extract verify_drone.star

* Extract windows.star

* Extract publish.star

* Remove unused code

* Fix formatting in main.star

scripts/drone/pipelines/integration_tests.star

@@ -0,0 +1,40 @@
+load(
+    'scripts/drone/steps/lib.star',
+    'identify_runner_step',
+    'download_grabpl_step',
+    'verify_gen_cue_step',
+    'wire_install_step',
+    'postgres_integration_tests_step',
+    'mysql_integration_tests_step',
+)
+
+load(
+    'scripts/drone/services/services.star',
+    'integration_test_services',
+    'integration_test_services_volumes',
+    'ldap_service',
+)
+
+load(
+    'scripts/drone/utils/utils.star',
+    'pipeline',
+)
+
+def integration_tests(trigger, ver_mode, edition):
+    services = integration_test_services(edition)
+    volumes = integration_test_services_volumes()
+    init_steps = [
+        download_grabpl_step(),
+        identify_runner_step(),
+        verify_gen_cue_step(edition="oss"),
+        wire_install_step(),
+    ]
+    test_steps = [
+        postgres_integration_tests_step(edition=edition, ver_mode=ver_mode),
+        mysql_integration_tests_step(edition=edition, ver_mode=ver_mode),
+    ]
+
+    return pipeline(
+        name='{}-integration-tests'.format(ver_mode), edition="oss", trigger=trigger, services=services, steps=init_steps + test_steps,
+        volumes=volumes
+    )