Replace only the word not the whole line. Also increase timeout of clone.

playbooks/kvm.yml

@@ -18,7 +18,7 @@
         target: '{{ hypervisor }}'
         storage: 'SSD1'
         format: 'qcow2'
-        timeout: 3000
+        timeout: 6000
       register: cloned
 
     - name: Wait 10 seconds for proxmox to register the new node

roles/common/tasks/main.yml

@@ -178,7 +178,8 @@
     name: '{{ inventory_hostname }}'
 
 - name: Fix hosts file
-  lineinfile: dest=/etc/hosts
-              regexp="ubuntu"
-              state=present
-              line="{{ inventory_hostname }}"
+  replace:
+    path: /etc/hosts
+    regexp: '(\s+)ubuntu(\s+.*)?$'
+    replace: '\1{{ inventory_hostname }}\2'
+    backup: yes