Delay bridge startup to ensure Synapse is up

Bridges start matrix-synapse.service as a dependency, but
Synapse is sometimes slow to start, while bridges are quick to
hit it and die (if unavailable).

They'll auto-restart later, but .. this still breaks `--tags=start`,
which doesn't wait long enough for such a restart to happen.

This attempts to slow down bridge startup enough to ensure Synapse
is up and no failures happen at all.

roles/matrix-bridge-appservice-discord/templates/systemd/matrix-appservice-discord.service.j2

@@ -14,6 +14,9 @@ Type=simple
 ExecStartPre=-/usr/bin/docker kill matrix-appservice-discord
 ExecStartPre=-/usr/bin/docker rm matrix-appservice-discord
 
+# Intentional delay, so that the homeserver (we likely depend on) can manage to start.
+ExecStartPre=/bin/sleep 5
+
 ExecStart=/usr/bin/docker run --rm --name matrix-appservice-discord \
 			--log-driver=none \
 			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \

roles/matrix-bridge-appservice-irc/templates/systemd/matrix-appservice-irc.service.j2

@@ -14,6 +14,9 @@ Type=simple
 ExecStartPre=-/usr/bin/docker kill matrix-appservice-irc
 ExecStartPre=-/usr/bin/docker rm matrix-appservice-irc
 
+# Intentional delay, so that the homeserver (we likely depend on) can manage to start.
+ExecStartPre=/bin/sleep 5
+
 ExecStart=/usr/bin/docker run --rm --name matrix-appservice-irc \
 			--log-driver=none \
 			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \

roles/matrix-bridge-mautrix-facebook/templates/systemd/matrix-mautrix-facebook.service.j2

@@ -21,6 +21,9 @@ ExecStartPre=/usr/bin/docker run --rm --name matrix-mautrix-facebook-db \
 			{{ matrix_mautrix_facebook_docker_image }} \
 			alembic -x config=/data/config.yaml upgrade head
 
+# Intentional delay, so that the homeserver (we likely depend on) can manage to start.
+ExecStartPre=/bin/sleep 5
+
 ExecStart=/usr/bin/docker run --rm --name matrix-mautrix-facebook \
 			--log-driver=none \
 			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \

roles/matrix-bridge-mautrix-telegram/templates/systemd/matrix-mautrix-telegram.service.j2

@@ -21,6 +21,9 @@ ExecStartPre=/usr/bin/docker run --rm --name matrix-mautrix-telegram-db \
 			{{ matrix_mautrix_telegram_docker_image }} \
 			alembic -x config=/data/config.yaml upgrade head
 
+# Intentional delay, so that the homeserver (we likely depend on) can manage to start.
+ExecStartPre=/bin/sleep 5
+
 ExecStart=/usr/bin/docker run --rm --name matrix-mautrix-telegram \
 			--log-driver=none \
 			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \

roles/matrix-bridge-mautrix-whatsapp/templates/systemd/matrix-mautrix-whatsapp.service.j2

@@ -14,6 +14,9 @@ Type=simple
 ExecStartPre=-/usr/bin/docker kill matrix-mautrix-whatsapp
 ExecStartPre=-/usr/bin/docker rm matrix-mautrix-whatsapp
 
+# Intentional delay, so that the homeserver (we likely depend on) can manage to start.
+ExecStartPre=/bin/sleep 5
+
 ExecStart=/usr/bin/docker run --rm --name matrix-mautrix-whatsapp \
 			--log-driver=none \
 			--user={{ matrix_user_uid }}:{{ matrix_user_gid }} \

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

@@ -17,7 +17,7 @@ ExecStartPre=-/usr/bin/docker rm matrix-synapse
 # Allow for some time before starting, so that media store can mount.
 # Mounting can happen later too, but if we start writing,
 # we'd write files to the local filesystem and fusermount will complain.
-ExecStartPre=/bin/sleep 5
+ExecStartPre=/bin/sleep 3
 {% endif %}
 
 ExecStart=/usr/bin/docker run --rm --name matrix-synapse \