Optimize uninstall tasks a bit

- forego removing Docker images - it's not effective anyway, because it
  only removes the last version.. which is a drop in the bucket, usually

- do not reload systemd - it's none of our business. `--tags=start`,
  etc., handle this

- combine all uninstall tasks under a single block, which only runs if
  we detect traces (a leftover systemd .service file) of the component.
  If no such .service is detected, we skip them all. This may lead to
  incorect cleanup in rare cases, but is good enough for the most part.

roles/custom/matrix-bridge-appservice-kakaotalk/tasks/setup_uninstall.yml

@@ -11,7 +11,7 @@
     state: stopped
     enabled: false
     daemon_reload: true
-  when: "matrix_appservice_kakaotalk_service_stat.stat.exists"
+  when: matrix_appservice_kakaotalk_service_stat.stat.exists | bool
 
 - name: Check existence of matrix-appservice-kakaotalk-node service
   ansible.builtin.stat:
@@ -24,7 +24,7 @@
     state: stopped
     enabled: false
     daemon_reload: true
-  when: "matrix_appservice_kakaotalk_node_service_stat.stat.exists"
+  when: matrix_appservice_kakaotalk_node_service_stat.stat.exists | bool
 
 - name: Ensure matrix-appservice-kakaotalk.service files don't exist
   ansible.builtin.file:
@@ -33,9 +33,4 @@
   with_items:
     - "{{ devture_systemd_docker_base_systemd_path }}/matrix-appservice-kakaotalk-node.service"
     - "{{ devture_systemd_docker_base_systemd_path }}/matrix-appservice-kakaotalk.service"
-  when: "matrix_appservice_kakaotalk_service_stat.stat.exists"
-
-- name: Ensure systemd reloaded after matrix-appservice-kakaotalk service files removal
-  ansible.builtin.service:
-    daemon_reload: true
-  when: "matrix_appservice_kakaotalk_service_stat.stat.exists or matrix_appservice_kakaotalk_node_service_stat.stat.exists"
+  when: matrix_appservice_kakaotalk_service_stat.stat.exists | bool or matrix_appservice_kakaotalk_node_service_stat.stat.exists | bool