fix: add docs for versioning and test changelog (#80)

docs/developer-guidelines.md

@@ -9,6 +9,20 @@
 - Lint and fix through `yarn lint --fix`
 - The JW organization requires personal access tokens for all of their repositories. In order to create a branch or pull request you'll need to [Generate a Personal Access Token](https://github.com/settings/tokens) and then [store it in your git config](https://stackoverflow.com/questions/46645843/where-to-store-my-git-personal-access-token/67360592). (For token permissions, `repo` should be sufficient.) 
 
+## Versioning and Changelog
+
+We use the [TriPSs/conventional-changelog-action](https://github.com/TriPSs/conventional-changelog-action) github [action](https://github.com/jwplayer/ott-web-app/actions/workflows/bump-version.yml) to do an automated version increment for any commit to the develop branch.  The type of version increment will be determined by the commit message(s) in the code being added as follows (see [Convential Commits](https://www.conventionalcommits.org/en/v1.0.0/) for more details):
+* `fix:` - perform a patch bump
+* `feat:` - perform a minor bump
+* commit body contains `BREAKING CHANGE:` - perform a major bump
+* `<type>!:` (i.e. `feat!:`) - perform a major bump
+
+In case there are multiple commits being merged, the biggest type of bump will be performed.
+
+The github action will update the project package.json, create a release tag in github, and update the changelog based on the commit messages in the code being merged.
+
+**Note**: In order to access the repository, the action relies on a personal access token, which is stored as `ACTION_TOKEN` in the [repository secrets](https://github.com/jwplayer/ott-web-app/settings/secrets/actions). If this token needs to be updated, please generate a [Personal Access Token](https://github.com/settings/tokens) with the `public_repo` scope.
+
 ## Git Commit Guidelines (conventional changelog)
 
 We use the conventional changelog thereby defining very precise rules over how our git commit messages can be formatted. This leads to **more readable messages** that are easy to follow when looking through the **project history**. But also, we allow the git commit messages to **generate the change log**.