Go through start.py when launching Synapse

This allows us to benefit from helpful things it does for us,
like enabling jemalloc: matrix-org/synapse#8553

We weren't going through `start.py` before, because it was causing some
conflict with our `docker run --user=...` stuff, but it doesn't seem
to be a problem anymore.

Having done this, we won't need to do things like
#941
anymore.

Author: spantaleev

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

@@ -18,7 +18,6 @@ ExecStart={{ matrix_host_command_docker }} run --rm --name {{ matrix_synapse_wor
 			--log-driver=none \
 			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \
 			--cap-drop=ALL \
-			--entrypoint=python \
 			--read-only \
 			--tmpfs=/tmp:rw,noexec,nosuid,size={{ matrix_synapse_tmp_directory_size_mb }}m \
 			--network={{ matrix_docker_network }} \
@@ -44,7 +43,7 @@ ExecStart={{ matrix_host_command_docker }} run --rm --name {{ matrix_synapse_wor
 			{{ arg }} \
 			{% endfor %}
 			{{ matrix_synapse_docker_image }} \
-			-m synapse.app.{{ matrix_synapse_worker_details.type }} -c /data/homeserver.yaml -c /data/{{ matrix_synapse_worker_config_file_name }}
+			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 }}

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

@@ -34,7 +34,6 @@ ExecStart={{ matrix_host_command_docker }} run --rm --name matrix-synapse \
 			--log-driver=none \
 			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \
 			--cap-drop=ALL \
-			--entrypoint=python \
 			--read-only \
 			--tmpfs=/tmp:rw,noexec,nosuid,size={{ matrix_synapse_tmp_directory_size_mb }}m \
 			--network={{ matrix_docker_network }} \
@@ -62,7 +61,7 @@ ExecStart={{ matrix_host_command_docker }} run --rm --name matrix-synapse \
 			{{ arg }} \
 			{% endfor %}
 			{{ matrix_synapse_docker_image }} \
-			-m synapse.app.homeserver -c /data/homeserver.yaml
+			run -m synapse.app.homeserver -c /data/homeserver.yaml
 
 ExecStop=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }} kill matrix-synapse 2>/dev/null'
 ExecStop=-{{ matrix_host_command_sh }} -c '{{ matrix_host_command_docker }} rm matrix-synapse 2>/dev/null'