ci: Add cocogitto/release.sh to perform releases.

[JamesXNelson]

Fixes #213
Fixes #218

• Add cog.toml to configure cocogitto, which generates changelogs and version tags
• Add tools/release.sh to perform a complete version bump + changelog update and github release for a plugin
• Updated README.md with instructions regarding the release process

[mofojed]

I tried running this bump.sh script on Mac, and it doesn't seem to work. The first time I ran it, it asked to install Cocogitto (good). I installed, then I ran again and it just shows a screen:

I then don't know what to press? I tried press Enter, does nothing; I hit "Q" and then I just get the following output:

[mofojed]

Also we should update the root level README with instructions on running the version bump for releases.

[JamesXNelson]

I tried running this bump.sh script on Mac, and it doesn't seem to work. The first time I ran it, it asked to install Cocogitto (good). I installed, then I ran again and it just shows a screen:

Try again w/ the latest. If you set your git remote origin to your fork, you can safely push test releases there.

[mofojed]

Looks like it's close! Getting an error on mac with the sed step:

(.venv) ➜  deephaven-plugins git:(main) ./tools/release.sh -d ui            
+ shift
+ ((  1 > 0  ))
+ case "$1" in
+ '[' -n '' ']'
+ grep -q ui
+ package=ui
+ shift
+ ((  0 > 0  ))
+ '[' -z ui ']'
+ grep -q plugins/ui /Users/bender/dev/deephaven/oss/deephaven-plugins/cog.toml
bender   -  2024-01-19 10:06:04  |--- Releasing package 'ui'
+ cd /Users/bender/dev/deephaven/oss/deephaven-plugins
+ cog bump --package ui --auto
        Found bug fix commit 0533cd
[pre-bump-ui]
[echo Updating ui to version 0.1.1]
Updating ui to version 0.1.1

[../../tools/update_version.sh ui 0.1.1]
sed: 1: "/Users/bender/dev/deeph ...": undefined label 'ender/dev/deephaven/oss/deephaven-plugins/plugins/ui/src/deephaven/ui/__init__.py'
Error: prehook run `../../tools/update_version.sh ui 0.1.1` failed
        All changes made during hook runs have been stashed on `cog_bump_ui-v0.1.1`
        you can run `git stash apply stash@0` to restore these changes.

[mofojed]

Great work! One minor change to the TODO (need to have an associated ticket for TODOs).

Also for posterity I don't know why I need to press Q when doing a release to advance. Seems odd, and I'll probably dig into that at some point.

[JamesXNelson]

Fixes #218