Adapt FileReader API to new events structure

[queengooborg]

This PR adapts the FileReader API to conform to the new events structure.

BCD PR: mdn/browser-compat-data#15131

[github-actions]

Preview URLs

• https://pr13301.content.dev.mdn.mozit.cloud/en-US/docs/Web/API/FileReader/abort_event
• https://pr13301.content.dev.mdn.mozit.cloud/en-US/docs/Web/API/FileReader/error_event
• https://pr13301.content.dev.mdn.mozit.cloud/en-US/docs/Web/API/FileReader/load_event
• https://pr13301.content.dev.mdn.mozit.cloud/en-US/docs/Web/API/FileReader/loadend_event
• https://pr13301.content.dev.mdn.mozit.cloud/en-US/docs/Web/API/FileReader/loadstart_event
• https://pr13301.content.dev.mdn.mozit.cloud/en-US/docs/Web/API/FileReader/progress_event
• https://pr13301.content.dev.mdn.mozit.cloud/en-US/docs/Web/API/FileReader

Flaws

Note! 6 documents with no flaws that don't need to be listed. 🎉

URL: /en-US/docs/Web/API/FileReader
Title: FileReader
on GitHub
Flaw count: 5

• bad_bcd_links:
  • no explanation!
  • no explanation!
  • no explanation!
  • no explanation!
  • no explanation!

External URLs

URL: /en-US/docs/Web/API/FileReader
Title: FileReader
on GitHub

No external URLs

---

URL: /en-US/docs/Web/API/FileReader/loadend_event
Title: FileReader: loadend event
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/API/FileReader/load_event
Title: FileReader: load event
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/API/FileReader/loadstart_event
Title: FileReader: loadstart event
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/API/FileReader/progress_event
Title: FileReader: progress event
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/API/FileReader/abort_event
Title: FileReader: abort event
on GitHub

No new external URLs

---

URL: /en-US/docs/Web/API/FileReader/error_event
Title: FileReader: error event
on GitHub

No new external URLs