refactor: delete all legacy Check_MK plugins in one task

tasks/install_checkmk_plugins.yml

 ---
-- name: delete legacy plugins
+- name: delete legacy Check_MK plugins
   file:
-    path: "/usr/lib/check_mk_agent/plugins/checkmk_dsmcad.sh"
+    path: "/usr/lib/check_mk_agent/plugins/{{ item }}"
     state: absent
+  loop:
+    - "checkmk_dsmcad.sh"
+    - "mk_logwatch"
 
 - name: install self-developed Check_MK plugins
   copy:
@@ -57,8 +60,3 @@
   import_tasks: "oracle/install_checkmk_plugins_oracle.yml"
   when: ( ansible_hostname is search("rosora") ) or
         ( ansible_hostname is search("rosettaora") )
-
-- name: remove legacy Check_MK plugin
-  file:
-    path: "/usr/lib/check_mk_agent/plugins/mk_inventory"
-    state: absent