Release Checklist 8.13

For one-time items such as blockers, it probably makes sense to check them off using github's markdown (that is, use the edit button to put an "x" between the square brackets. For all standard "testing" and "history" items that are copied from the template, though, please just go ahead and delete them entirely when they're done; since this list is long, it's otherwise difficult to locate the un-checked items.

[ ] Blockers: https://github.com/racket/racket/issues/4978

History Updates

• {Sam Tobin-Hochstadt samth@ccs.neu.edu}
  • Typed Racket Updates: update HISTORY (updates should show v8.13 as the most current version; include the text "merge" in the commit message, or tell me if there are no such changes.)

Testing

• {Blockers}