public Kv charset(Charset charset) {
        checkNotNull(charset);
        internalProperties.putString(TableFormatConstants.FORMAT_CHARSET, charset.name());
        return this;
    }
Sets the charset of the text.

@param charset The charset of the text.
inlong-sort/sort-formats/format-row/format-kv/src/main/java/org/apache/inlong/sort/formats/kv/Kv.java