Add workflow to automatically create a release

.github/workflows/release.yml

@@ -1,17 +1,17 @@
-name: Update the v1 branch when a release is published
+name: Create a Release
 on:
-  release:
-    types: [published]
+  workflow_dispatch:
 permissions:
-  contents: read
+  contents: write # for creating release
 
 jobs:
   release:
     runs-on: ubuntu-latest
-    permissions:
-      contents: write # for git push
     steps:
     - uses: actions/checkout@v4
       with:
         fetch-depth: 0
-    - run: git push origin HEAD:v1
+    - uses: ./
+      with:
+        ruby-version: '3.3'
+    - run: ruby release.rb

.github/workflows/update-v1-branch.yml

@@ -0,0 +1,15 @@
+name: Update the v1 branch when a release is published
+on:
+  release:
+    types: [published]
+permissions:
+  contents: write # for git push
+
+jobs:
+  update_branch:
+    runs-on: ubuntu-latest
+    steps:
+    - uses: actions/checkout@v4
+      with:
+        fetch-depth: 0
+    - run: git push origin HEAD:v1

release.rb

@@ -0,0 +1,17 @@
+require 'json'
+
+def run(command_line)
+  puts "$ #{command_line}"
+  output = `#{command_line}`
+  puts output
+  raise $?.inspect unless $?.success?
+  output
+end
+
+latest_release_tag = run 'gh release view --json tagName'
+latest_release_tag = JSON.load(latest_release_tag).fetch('tagName')
+
+raise latest_release_tag unless latest_release_tag =~ /\Av(\d+).(\d+).(\d+)\z/
+tag = "v#{$1}.#{Integer($2)+1}.0"
+
+run "gh release create --generate-notes --latest #{tag}"