diagnostics_channel.hasSubscribers repro (workerd PR #6601)
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typeof channel.hasSubscribers: "function"
Boolean(channel.hasSubscribers) with 0 subscribers: true
Boolean(channel.hasSubscribers) with 1 subscriber: true
Boolean(channel.hasSubscribers) after unsubscribe: true
descriptor has get?: false
descriptor has value?: true
typeof tracingChannel.hasSubscribers: "undefined"
Boolean(tracingChannel.hasSubscribers) with 0 subscribers: false

Expected (Node.js):
  typeof channel.hasSubscribers === "boolean"
  Boolean(channel.hasSubscribers) with 0 subscribers === false

Actual (workerd, pre-fix):
  typeof channel.hasSubscribers === "function"
  Boolean(channel.hasSubscribers) with 0 subscribers === true  <-- bug