State explicitly in docs that 'close' does not take any arguments

[ryzokuken]

In the http2 module, the Http2Session class emits an event named close, which is documented at https://github.com/nodejs/node/blob/master/doc/api/http2.md#event-close.

As evident from the following function from lib/internal/http2/core.js, the event does not expect any arguments:

function emitClose(self, error) {
  if (error)
    self.emit('error', error);
  self.emit('close');
}

However, the current docs do a poor job of communicating this, therefore creating confusion.

Thus, the fact that the close event does not expect arguments should be explicitly mentioned in the docs.

The exact source can be found at:

node/doc/api/http2.md

Lines 126 to 131 in 6376d43

	#### Event: 'close'
	<!-- YAML
	added: v8.4.0
	-->
	The `'close'` event is emitted once the `Http2Session` has been destroyed.

[ryzokuken]

cc @mcollina @nodejs/http2 does this look good? Feel free to suggest any structural changes, and I'd base the remaining issues on the finalized structure.

[jasnell]

This is fine. Want to open a PR?

[ryzokuken]

@jasnell

At nodejs/help#877 (comment), @mcollina had suggested opening a few "good first issues", and that was why I was interested in the structure of the issue (so that first time contributors find it convenient). That said, I'm willing to open a PR if that's what you're propose, but that wasn't the intent when I opened the issue.

[mcollina]

Added the "good first issue tag"