doc: pass string to `textEncoder.encode` as input
Input of textEncoder.encode should be string, not array.
Refs: https://nodejs.org/dist/latest-v19.x/docs/api/util.html#textencoderencodeinput
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Input of textEncoder.encode should be string, not array.
Refs: https://nodejs.org/dist/latest-v19.x/docs/api/util.html#textencoderencodeinput