В
const fetch = require('node-fetch')
const http = require('http')
const https = require('https')
const httpAgent = new http.Agent({ keepAlive: true })
const httpsAgent = new https.Agent({ keepAlive: true, rejectUnauthorized: false })
... agent: httpsAgentполучаю в отправленных заголовках "connection: close"
хотя должно быть keep-alive
