Add 0.2.8 to changelog

7 jobs for master in 3 minutes and 9 seconds (queued for 3 seconds)
Status Name Job ID Coverage
  Build
passed build:nightly #21371

00:01:39

passed build:no_std #21373

00:01:17

passed build:redox #21372

00:01:26

passed build:stable #21370

00:01:16

 
  Test
passed test:benches #21376

00:01:26

passed test:nightly #21375

00:01:29

passed test:stable #21374

00:01:14