Added DOWNLOAD_EXTRA_CONFIGS (#3679)

scripts/start-setupEnvVariables

@@ -17,6 +17,7 @@ handleDebugMode
 : "${DOWNLOAD_DEFAULTS:=}"
 : "${DOWNLOAD_DEFAULT_CONFIGS:=}"
 : "${SKIP_DOWNLOAD_DEFAULTS:=false}"
+: "${DOWNLOAD_EXTRA_CONFIGS:=}"
 
 if isTrue "${REPLACE_ENV_IN_PLACE}"; then
   log "Replacing env variables in ${REPLACE_ENV_PATHS} that match the prefix '$REPLACE_ENV_VARIABLE_PREFIX' ..."
@@ -54,6 +55,15 @@ if isFalse "$SKIP_DOWNLOAD_DEFAULTS"; then
   fi
 fi
 
+if [[ $DOWNLOAD_EXTRA_CONFIGS ]]; then
+  mc-image-helper mcopy \
+    --to /data \
+    --skip-existing \
+    --skip-up-to-date=false \
+    --quiet-when-skipped \
+    "$DOWNLOAD_EXTRA_CONFIGS"
+fi
+
 if [[ ${PATCH_DEFINITIONS} ]]; then
   log "Applying patch definitions from ${PATCH_DEFINITIONS}"
   mc-image-helper patch \