fix pruning args (#626)

Author: wlawt

reth/reth-entrypoint

@@ -33,7 +33,8 @@ else
 fi
 
 # Add pruning for base
-if [[ "$NODE_TYPE" == "base" && -n "${RETH_PRUNING_ARGS+x}" = x ]]; then
+if [[ "$NODE_TYPE" == "base" && "${RETH_PRUNING_ARGS+x}" = x ]]; then
+    echo "Adding pruning arguments: $RETH_PRUNING_ARGS"
     ADDITIONAL_ARGS="$ADDITIONAL_ARGS $RETH_PRUNING_ARGS"
 fi