Add release notes for Review Board 4.0.4.
Review Request #2234 — Created Sept. 23, 2021 and updated
This release adds explicit support for Amazon SES, upgrades CodeMirror
for new features and fixes, addresses a few regressions, and fixes a
long-standing issue that could occur with Status Updates for automated
Built the release notes. Checked for build errors, bad links, and
Reviewed at https://reviews.reviewboard.org/r/11734/
This is by cyuan.......