Add UI for timesheet entry delete

[BeckyPollard]

RE: Add UI for deleting content

Summary of changes:

• Add a button to handle deletion of entry.
• Add a confirmation prompt before delete, to avoid heartbreaks.
  • Featuring full keyboard accessibility from the accessible modal dialog component package react-modal.
  • Very basic styling on the modal, pending design directions for app.
  • New reusable component for these kinds of action prompts: ConfirmModal ✨
• Add esModuleInterop to tsconfig.

Relies on:

• Handle deleting single timesheet entries before submit. #35 tt-api#41
• Invalidate entry's sheet collection when delete tt-api#45

NEW BUTTON	CONFIRM PROMPT

---

Feedback, nitpicks, and/or corrections encouraged. 🤖