chore: Make a custom semantic-release action with build step

[eKoopmans]

This PR should fix the semantic-release process to squeeze the build step in between when the NPM version is bumped and when the changes are committed and pushed.

The goal, in semantic-release:

1. commit-analyzer > analyzeCommits determines what kind of release to make
2. semantic-release internally determines the new package version based on that release info
3. ... other steps happen, e.g. generateNotes
4. npm > prepare updates the package.json version
5. semantic-release.plugin.build.js (my new plugin) runs npm run build, generating a new dist folder
6. git > prepare creates the release commit with changes from dist and package*.json
7. ... other steps happen, e.g. npm publishing

In the future I'll be removing dist from git tracking, but regardless I want that build to happen in the middle so the bundle files can be generated with the right version and copyright etc.

Resources:

• BrightspaceUI/actions/semantic-release
• semantic-release repo, configuration, plugins (plugin steps were useful)
  • there was pretty poor documentation about using local plugins and custom config file locations
• plugins in order of execution: commit-analyzer, github, npm, release-notes-generator, git
• other existing semantic-release actions: https://github.com/codfish/semantic-release-action, https://github.com/cycjimmy/semantic-release-action
• plugin development: https://semantic-release.gitbook.io/semantic-release/developer-guide/plugin
• plugin steps:

  verifyConditions
      github
      npm
      git
  analyzeCommits
      commit-analyzer
  verifyRelease
  generateNotes
      release-notes-generator
  prepare
      npm
      *MY BUILD PLUGIN*
      git
  publish
      github
      npm
  addChannel
      github
      npm
  success
      github
  fail
      github