Add documentation for available audit event types

config/audit_events/types/manually_trigger_housekeeping.yml

...administration/audit_event_streaming/audit_event_types.md

..._events/types/allow_merge_on_skipped_pipeline_updated.yml

...ents/types/google_cloud_logging_configuration_created.yml

...ents/types/google_cloud_logging_configuration_deleted.yml

...ents/types/google_cloud_logging_configuration_updated.yml

...types/group_push_rules_reject_deny_delete_tag_updated.yml

ee/config/audit_events/types/remove_ssh_key.yml

lefthook.yml

lib/tasks/gitlab/audit_event_types/audit_event_types.rake

lib/tasks/gitlab/audit_event_types/check_docs_task.rb

lib/tasks/gitlab/audit_event_types/compile_docs_task.rb

...s/gitlab/audit_event_types/audit_event_types_rake_spec.rb

spec/tasks/gitlab/audit_event_types/check_docs_task_spec.rb

.../tasks/gitlab/audit_event_types/compile_docs_task_spec.rb

tooling/audit_events/docs/templates/audit_event_types.md.erb