public static Optional<String> getValueAsString(final ObjectNode node, final String key) {
    return getValue(node, key).map(JsonNode::asText);
  }
Get the string representation of the value at {@code key}. For example, a numeric value like 5
will be returned as "5".

@param node The {@code ObjectNode} from which the value will be extracted.
@param key The key corresponding to the value to extract.
@return The value at the given key as a string if it exists.
config/src/main/java/org/hyperledger/besu/config/JsonUtil.java