feat(nfs): add per-share sync option (default true) to fix rsync I/O errors

nfs/run.sh

@@ -18,6 +18,7 @@ else
         NETWORK=$(jq -r ".shares[${i}].allowed_network" "${CONFIG}")
         READ_ONLY=$(jq -r ".shares[${i}].read_only" "${CONFIG}")
         ROOT_SQUASH=$(jq -r ".shares[${i}].root_squash" "${CONFIG}")
+        SYNC=$(jq -r ".shares[${i}].sync" "${CONFIG}")
         MOUNT_PATH="/${FOLDER}"
 
         if [ "${READ_ONLY}" = "true" ]; then
@@ -31,6 +32,11 @@ else
         else
             OPTIONS="${OPTIONS},no_root_squash"
         fi
+
+        if [ "${SYNC}" = "true" ]; then
+            OPTIONS="${OPTIONS},sync"
+        fi
+
         OPTIONS="${OPTIONS},insecure"
 
         bashio::log.info "Exporting ${MOUNT_PATH} to ${NETWORK} (${OPTIONS})..."