Add callbacks testcase for no hosts remaining

This change adds a new testcase to the ansible-playbook-callbacks
integration test that checks the callbacks fired when all hosts fail.

This provides a simple regression test for issue 81549.

test/integration/targets/ansible-playbook-callbacks/no-hosts-remaining/callbacks_list.expected

@@ -0,0 +1,10 @@
+ 1 __init__
+10 v2_on_any
+ 1 v2_playbook_on_no_hosts_remaining
+ 1 v2_playbook_on_play_start
+ 1 v2_playbook_on_start
+ 1 v2_playbook_on_stats
+ 2 v2_playbook_on_task_start
+ 1 v2_runner_on_failed
+ 1 v2_runner_on_ok
+ 2 v2_runner_on_start

test/integration/targets/ansible-playbook-callbacks/no-hosts-remaining/exit_code.expected

@@ -0,0 +1 @@
+2

test/integration/targets/ansible-playbook-callbacks/no-hosts-remaining/test.yml

@@ -0,0 +1,12 @@
+---
+- hosts: localhost
+  gather_facts: no
+  tasks:
+    - debug:
+        msg: Hello, world!
+
+    - fail:
+        msg: Oh dear
+
+    - debug:
+        msg: We don't get here