v1.2.0.1

[schloerke]

• [x] devtools::release(check = TRUE) (don't release)
• [x] bump version
• [x] Get testing app approval: https://github.com/rstudio/shinycoreci-apps/pull/108
• [x] Pass all GHA checks
• [x] devtools::check_win_devel()
• [x] devtools::check_win_release()
• [x] devtools::check_win_oldrelease()
• [x] revdepcheck::revdep_check()
• [x] Update cran comments
• [x] devtools::release()
• [x] CRAN accepts
• [x] Squash merge RC branch into master
• [x] Tag release
• [x] Create GitHub release, and copy NEWS items into release notes
• [x] Delete RC branch
• [x] Bump dev version number
• [x] Blog / tweet