feat(docs): Adds an "Edit this page on GitHub" button to docs pages

[rusackas]

SUMMARY

• Changes Docusaurus config to take you to the actual edit link, so you can edit a given page on GitHub (or open a PR easily)
• "Swizzles" the docs layout in order to add a new Edit button component.
• Adds the component, as seen in this here GIF:

BEFORE/AFTER SCREENSHOTS OR ANIMATED GIF

TESTING INSTRUCTIONS

ADDITIONAL INFORMATION

• Has associated issue:
• Required feature flags:
• Changes UI
• Includes DB Migration (follow approval process in SIP-59)
  • Migration is atomic, supports rollback & is backwards-compatible
  • Confirm DB migration upgrade and downgrade tested
  • Runtime estimates and downtime expectations provided
• Introduces new feature or API
• Removes existing feature or API

[sfirke]

@rusackas this button works for me, I love it. But does it conflict with the BugHerd button? I'm not sure but I remember it being in the same place and now I don't see the BH button anywhere on a docs page.

[rusackas]

I have the same curiosity... I'm not sure what happened to the BugHerd button. That needs investigation. Happy to move this to fit if needed when we figure that out.