fix(release): manually release a major version

There was an issue with a major release, so this manual-releases.md
change is to release a new major version.

Reference: #260

BREAKING CHANGE: You must switch from `dom-testing-library` to `@testing-library/dom`

Author: Kent C. Dodds

other/manual-releases.md

@@ -41,4 +41,4 @@ change is to release a new patch version.
 Reference: #<the number of a relevant pull request, issue, or commit>
 ```
 
-The number of times we've had to do a manual release is: 4
+The number of times we've had to do a manual release is: 5