[Stream] Added content for downloading stream live videos (#4239)

* Added content for downloading stream live videos

* Added Kyle's feedback about ready state

content/stream/stream-live/download-stream-live-videos.md

+---
+pcx-content-type: how-to
+title: Download live stream videos
+---
+
+# Download live stream videos
+
+You can enable downloads for live stream videos from the Cloudflare dashboard. Videos are available for download after they enter the **Ready** state.
+
+1. Log in to your [Cloudflare dashboard](https://dash.cloudflare.com) and select your account.
+2. Click **Stream** > **Live Inputs**.
+3. Click a live input from the list to select it.
+4. Under **Videos created by live input**, locate your video and click to select it.
+5. Under **Settings**, select **Enable MP4 Downloads**.
+6. Click **Save**. You will see a progress bar as the video generates a download link.
+7. When the download link is ready, under **Download URL**, copy the URL and enter it in a browser to download the video.