Resolve "Warn in Web Editor when user navigates away"

What does this MR do?

While user is editing a file, it this MR prevents them from navigating away accidentally without committing changes.

This MR prevents navigation by adding a 'beforeunload' event listener to the window. The event listener is removed when the user clicks the commit button

What are the relevant issue numbers?

closing issue #53728 (closed)

Does this MR meet the acceptance criteria?

• Changelog entry added, if necessary
• Documentation created/updated
• Tests added for this feature/bug
• Conforms to the code review guidelines
• Conforms to the merge request performance guidelines
• Conforms to the style guides
• Conforms to the database guides
• Link to e2e tests MR added if this MR has Requires e2e tests label. See the Test Planning Process.

Closes #53728 (closed)