add publish gh action; bump dep

.github/workflows/publish.yml

@@ -0,0 +1,21 @@
+name: Ruby
+
+on:
+  release:
+    types: [published]
+
+jobs:
+  publish:
+    permissions:
+      id-token: write
+    runs-on: ubuntu-latest
+    name: Publish to RubyGems
+    steps:
+    - uses: actions/checkout@v4
+    - name: Set up Ruby
+      uses: ruby/setup-ruby@v1
+      with:
+        ruby-version: 3.3.5
+        bundler-cache: true
+    - name: Publish
+      uses: rubygems/release-gem@v1

Gemfile.lock

@@ -1,7 +1,7 @@
 PATH
   remote: .
   specs:
-    alda-rb (0.3.1)
+    alda-rb (0.4.0)
       bencode
       colorize
 
@@ -28,4 +28,4 @@ DEPENDENCIES
   rdoc
 
 BUNDLED WITH
-   2.5.18
+   2.5.20

lib/alda-rb/version.rb

@@ -7,5 +7,5 @@ module Alda
 	# The version number of alda-rb.
 	#
 	# The same as that in alda-rb gem spec.
-	VERSION = '0.3.1'
+	VERSION = '0.4.0'
 end