Switch to trusted publishing workflow and run it on version.rb changes

.github/workflows/actions.yml

@@ -4,7 +4,6 @@ on:
   pull_request:
   push:
     branches:
-      - master
       - main
 
 jobs:

.github/workflows/publish.yml

@@ -0,0 +1,26 @@
+name: Publish to RubyGems.org
+
+on:
+  push:
+    branches: main
+    paths: lib/zendesk_apps_support/version.rb
+  workflow_dispatch:
+
+jobs:
+  publish:
+    runs-on: ubuntu-latest
+    environment: rubygems-publish
+    if: github.repository_owner == 'zendesk'
+    permissions:
+      id-token: write
+      contents: write
+    steps:
+      - uses: actions/checkout@v4
+      - name: Set up Ruby
+        uses: ruby/setup-ruby@v1
+        with:
+          bundler-cache: false
+
+      - name: Install dependencies
+        run: bundle install
+      - uses: rubygems/release-gem@v1

README.md

@@ -15,9 +15,24 @@ Very likely you want to try out your changes with the use of ZAT. See [ZAT](http
 This project uses Rspec, which can be run with `bundle exec rake`.
 
 ## Contribute
-* Put up a PR into the master branch.
+* Put up a PR into the main branch.
 * CC and get two +1 from @zendesk/wattle.
 
+### Releasing a new version
+A new version is published to RubyGems.org every time a change to `version.rb` is pushed to the `main` branch.
+In short, follow these steps:
+1. Update `version.rb`,
+2. run `bundle lock` to update `Gemfile.lock`,
+3. merge this change into `main`, and
+4. look at [the action](https://github.com/zendesk/zendesk_apps_support/actions/workflows/publish.yml) for output.
+
+To create a pre-release from a non-main branch:
+1. change the version in `version.rb` to something like `1.2.0.pre.1` or `2.0.0.beta.2`,
+2. push this change to your branch,
+3. go to [Actions → “Publish to RubyGems.org” on GitHub](https://github.com/zendesk/zendesk_apps_support/actions/workflows/publish.yml),
+4. click the “Run workflow” button,
+5. pick your branch from a dropdown.
+
 ## Bugs
 Bugs can be reported as an issue here on github, or submitted to support@zendesk.com. By mentioning this project it will assigned to the right team.
 

lib/zendesk_apps_support/version.rb

@@ -0,0 +1,3 @@
+module ZendeskAppsSupport
+  VERSION = "4.42.0"
+end

zendesk_apps_support.gemspec

@@ -1,8 +1,10 @@
 # frozen_string_literal: true
 
+require_relative 'lib/zendesk_apps_support/version'
+
 Gem::Specification.new do |s|
   s.name        = 'zendesk_apps_support'
-  s.version     = '4.42.0'
+  s.version     = ZendeskAppsSupport::VERSION
   s.license     = 'Apache License Version 2.0'
   s.authors     = ['James A. Rosen', 'Likun Liu', 'Sean Caffery', 'Daniel Ribeiro']
   s.email       = ['dev@zendesk.com']