MDS Date cell

[juanca]

https://www.pivotaltracker.com/story/show/180679135

Note for reviewer(s)

I ended up upgrading a bunch of testing libraries to have a better label on the calendar widget. Unfortunately, it didn't work because there is a bug with something inside testing-library. For now, I changed the label on the buttons to be generic.

PR upkeep checklist

• [x] Change log entry
• [x] Label(s)
• [x] Assignee(s)
• [x] Deployment URL: https://mavenlink.github.io/design-system/mds-date-cell/
• [x] (When ready for review) Reviewer(s)
• [x] Green Bigmaven CI check: https://github.com/mavenlink/mavenlink/pull/27963
• [ ] DevQA on Bigmaven staging (e.g. does the work need to be imported in the internal design system?)