…98f)

if deployment succeeds, the build workflow will create a github
release, along with a matching a git tag.

the placeholder release description should be updated, and the
attached installers.zip replaced with separate installer packages
contained within itself.

the workflow has to attach all artifacts as a single zip because
the relevant action cannot upload multiple files to a release yet
(not without insane workflow step duplication.)

(connectivity note removed because it should be obvious)

…to gh-release

+ updated build candidates
+ ubuntu package upload optimized
+ publish.sh sanitized a bit

the deploy workflow's distro list needs to be updated periodiclly.

particularly, the ubuntu versions list must be kept up-to-date
with their current latest short term and long term versions.
otherwise it will break deploy workflow, because canonical moves
repos into archives fairly often. if our deploy workflow tries to
build for a ubuntu version that has been archived, it will fail.

for example, as of this commit, ubuntu19.04 repo has already been
archived, so I had to use 19.10 in the build list instead.

(thanks @mominul)

Co-Authored-By: Muhammad Mominul Huque <mominul2082@gmail.com>