add check to see if key exists

tasks/setup-Debian.yml

@@ -1,13 +1,20 @@
 ---
+- name: Check if key is present
+  stat:
+    path: /etc/apt/trusted.gpg.d/pgdg.asc
+  register: st_pgdg
+
 - name: Add PostgreSQL APT repo
   command: sh -c 'echo "deb http://apt.postgresql.org/pub/repos/apt $(lsb_release -cs)-pgdg main" > /etc/apt/sources.list.d/pgdg.list'
   become: true
+  when: not st_pgdg.stat.exists
 
 - name: Import and Write gpg key to pgdg.asc
   get_url:
     url: https://www.postgresql.org/media/keys/ACCC4CF8.asc
     dest: /etc/apt/trusted.gpg.d/pgdg.asc
   become: true
+  when: not st_pgdg.stat.exists
 
 - name: Update cache
   apt: update_cache=yes state=latest