Updates text of generate-webhook-url-basic.md to replace the use of
the "Create the channel" step.
Removes {!create-channel.md!} from all the integrations docs that
also include {!generate-webhook-url-basic.md!}.
Fixes#32269.
Besides reformatting the Netlify doc, this commit also updates the
instructions to match some UI changes in Netlify. The "Outgoing Webhook"
menu is now called "HTTP Post request".
Part of #29592.
markdown-include is GPL licensed.
Also, rewrite it as a block processor, so that it works correctly
inside indented blocks.
Signed-off-by: Anders Kaseorg <anders@zulip.com>
oscar
PieterCK
Mateusz Mandera
Tim Abbott
Satyam Bansal
Anders Kaseorg
Lenny Jagielski