Support literal newlines in motd from docker env files (#4087)

Dockerfile

@@ -55,7 +55,7 @@ RUN easy-add --var os=${TARGETOS} --var arch=${TARGETARCH}${TARGETVARIANT} \
   --from ${GITHUB_BASEURL}/itzg/{{.app}}/releases/download/{{.version}}/{{.app}}_{{.version}}_{{.os}}_{{.arch}}.tar.gz
 
 # renovate: datasource=github-releases packageName=itzg/mc-image-helper versioning=loose
-ARG MC_HELPER_VERSION=1.59.1
+ARG MC_HELPER_VERSION=1.60.0
 ARG MC_HELPER_BASE_URL=${GITHUB_BASEURL}/itzg/mc-image-helper/releases/download/${MC_HELPER_VERSION}
 # used for cache busting local copy of mc-image-helper
 ARG MC_HELPER_REV=1

files/property-definitions.json

@@ -41,7 +41,7 @@
   "max-players": {"env": "MAX_PLAYERS"},
   "max-tick-time": {"env": "MAX_TICK_TIME"},
   "max-world-size": {"env": "MAX_WORLD_SIZE"},
-  "motd": {"env": "MOTD"},
+  "motd": {"env": "MOTD", "translateLiteralNewlines":  true},
   "network-compression-threshold": {"env": "NETWORK_COMPRESSION_THRESHOLD"},
   "online-mode": {"env": "ONLINE_MODE"},
   "op-permission-level": {"env": "OP_PERMISSION_LEVEL"},