fix(plan): add await block to ensure parallel tasks completion in add_inventory_hostnames

- Wrap parallelize block with await to ensure all tasks complete before proceeding
- Add notification to indicate inventory update completion

Author: CoMfUcIoS

spec/acceptance/peadm_spec/plans/add_inventory_hostnames.pp

@@ -4,10 +4,13 @@
   $t = get_targets('*')
   wait_until_available($t)
 
-  parallelize($t) |$target| {
-    $fqdn = run_command('hostname -f', $target)
-    $target.set_var('certname', $fqdn.first['stdout'].chomp)
-    $command = "yq eval '(.groups[].targets[] | select(.uri == \"${target.uri}\").name) = \"${target.vars['certname']}\"' -i ${inventory_file}"
-    run_command($command, 'localhost')
-  }
+  await(
+    parallelize($t) |$target| {
+      $fqdn = run_command('hostname -f', $target)
+      $target.set_var('certname', $fqdn.first['stdout'].chomp)
+      $command = "yq eval '(.groups[].targets[] | select(.uri == \"${target.uri}\").name) = \"${target.vars['certname']}\"' -i ${inventory_file}"
+      run_command($command, 'localhost')
+    }
+  )
+  notify { 'Inventory updated': }
 }