Feat/hearts 2024 announcement

[itsalaidbacklife]

This updates the AnnouncementDialog to:

1. Support optional startTime and endTime, hiding the announcement outside their bounds, unless specified
2. Allows embedding links inside paragraphs

Issue number

N/A

Please check the following

• Do the tests still pass? (see Run the Tests)
• Is the code formatted properly? (see Linting (Formatting))
• For New Features:
  • Have tests been added to cover any new features or fixes?
  • Has the documentation been updated accordingly?

Please describe additional details for testing this change

[itsalaidbacklife]

I tested this locally and it works, but I'm not sure how to test it. The weird thing is that this component is so coupled to the announcementData.js file without using props. For that reason, I'm unsure how to set up a test to force the announcement data to have different values. Maybe the trick is to expose it to the window or as a store?

This might be a usecase for component testing, but I'm similarly unsure how to stub the annoucement data