Do not delete and re-create Synapse worker configs needlessly

We had checks to avoid stopping/deleting systemd services for workers
that used to exist and will continue to exist, but we were deleting
config files for workers each time.. Only to recreate them again later.

This lead to:

- too many misleading "changed" tasks
- too much unnecessary work
- potential failures during playbook execution possibly leaving the
  system in a bad state (no worker config files)

roles/custom/matrix-synapse/tasks/synapse/workers/setup_install.yml

@@ -7,12 +7,16 @@
     use_regex: true
   register: matrix_synapse_workers_current_config_files
 
+- set_fact:
+    matrix_synapse_enabled_worker_names: "{{ matrix_synapse_workers_enabled_list | map(attribute='name') }}"
+
 # This also deletes some things which we need. They will be recreated below.
-- name: Ensure previous worker configs are cleaned
+- name: Ensure unnecessary worker configs are cleaned
   ansible.builtin.file:
     path: "{{ item.path }}"
     state: absent
   with_items: "{{ matrix_synapse_workers_current_config_files.files }}"
+  when: "not ansible_check_mode and (item.path | basename | replace ('worker.', '') | replace('.yaml', '')) not in matrix_synapse_enabled_worker_names"
 
 - name: Determine current worker systemd services
   ansible.builtin.find:
@@ -27,13 +31,14 @@
     state: stopped
     enabled: false
   with_items: "{{ matrix_synapse_workers_current_systemd_services.files }}"
-  when: "not ansible_check_mode and item.path | basename not in devture_systemd_service_manager_services_list | map(attribute='name')"
+  when: "not ansible_check_mode and (item.path | basename | replace('.service', '')) not in matrix_synapse_enabled_worker_names"
 
 - name: Ensure unnecessary worker systemd services are cleaned
   ansible.builtin.file:
     path: "{{ item.path }}"
     state: absent
   with_items: "{{ matrix_synapse_workers_current_systemd_services.files }}"
+  when: "not ansible_check_mode and (item.path | basename | replace('.service', '')) not in matrix_synapse_enabled_worker_names"
 
 - name: Ensure creation of worker systemd service files and configuration files
   ansible.builtin.include_tasks: "{{ role_path }}/tasks/synapse/workers/util/setup_files_for_worker.yml"