Enhance release notes automation (#3751) (#3776)

* Bump versions
* It now tabs every line included in the Release Notes section of
  the PR template

(cherry picked from commit b00b22a1

)

# Conflicts:
#	.github/workflows/config/release-notes.json
#	.github/workflows/release-notes.yml

Co-authored-by: Jack Koenig <koenig@sifive.com>