Suppress errors in docker kill/rm calls for Synapse workers

We do the same everywhere else. This is an omission.

roles/matrix-synapse/templates/synapse/systemd/matrix-synapse-worker.service.j2

@@ -8,8 +8,8 @@ After=matrix-synapse.service
 Type=simple
 Environment="HOME={{ matrix_systemd_unit_home_path }}"
 
-ExecStartPre=-{{ matrix_host_command_docker }} kill {{ matrix_synapse_worker_container_name }}
-ExecStartPre=-{{ matrix_host_command_docker }} rm {{ matrix_synapse_worker_container_name }}
+ExecStartPre=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }} kill {{ matrix_synapse_worker_container_name }} 2>/dev/null || true'
+ExecStartPre=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }} rm {{ matrix_synapse_worker_container_name }} 2>/dev/null || true'
 
 # Intentional delay, so that the homeserver can manage to start.
 ExecStartPre={{ matrix_host_command_sleep }} 5
@@ -46,8 +46,8 @@ ExecStart={{ matrix_host_command_docker }} run --rm --name {{ matrix_synapse_wor
 			run -m synapse.app.{{ matrix_synapse_worker_details.type }} -c /data/homeserver.yaml -c /data/{{ matrix_synapse_worker_config_file_name }}
 
 
-ExecStop=-{{ matrix_host_command_docker }} kill {{ matrix_synapse_worker_container_name }}
-ExecStop=-{{ matrix_host_command_docker }} rm {{ matrix_synapse_worker_container_name }}
+ExecStop=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }} kill {{ matrix_synapse_worker_container_name }} 2>/dev/null || true'
+ExecStop=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }} rm {{ matrix_synapse_worker_container_name }} 2>/dev/null || true'
 
 ExecReload={{ matrix_host_command_docker }} exec {{ matrix_synapse_worker_container_name }} /bin/sh -c 'kill -HUP 1'
 Restart=always