private JsonNode objectToJson(Object object) {
        ObjectMapper objectMapper = new ObjectMapper();
        try {
            return objectMapper.readTree(objectMapper.writeValueAsString(object));
        } catch (IOException ex) {
            throw new RuntimeException(ex);
        }
    }
Creates ConfigSource from java.util.Properties as-is.

<p>Users and plugins MUST NOT call this directly. No any compatibility is guaranteed.
embulk-deps/src/main/java/org/embulk/deps/config/ConfigLoaderDelegateImpl.java