test helper: adjusted unit tests using new features (#9563)

tests/unit/plugins/modules/test_xfconf.yaml

@@ -4,6 +4,16 @@
 # SPDX-License-Identifier: GPL-3.0-or-later
 
 ---
+anchors:
+  environ: &env-def {environ_update: {LANGUAGE: C, LC_ALL: C}, check_rc: false}
+  version_out: &version-output |
+    xfconf-query 4.18.1
+
+    Copyright (c) 2008-2023
+        The Xfce development team. All rights reserved.
+
+    Please report bugs to <https://gitlab.xfce.org/xfce/xfconf>.
+test_cases:
 - id: test_missing_input
   input: {}
   output:
@@ -25,15 +35,9 @@
   mocks:
     run_command:
     - command: [/testbin/xfconf-query, --version]
-      environ: &env-def {environ_update: {LANGUAGE: C, LC_ALL: C}, check_rc: false}
+      environ: *env-def
       rc: 0
-      out: &version-output |
-        xfconf-query 4.18.1
-
-        Copyright (c) 2008-2023
-            The Xfce development team. All rights reserved.
-
-        Please report bugs to <https://gitlab.xfce.org/xfce/xfconf>.
+      out: *version-output
       err: ""
     - command: [/testbin/xfconf-query, --channel, xfwm4, --property, /general/inactive_opacity]
       environ: *env-def