CI: switch to GitHub OIDC for gem publishing

Author: nicolaiarocci

.github/workflows/release.yml

@@ -7,6 +7,7 @@ on:
 
 permissions:
   contents: write
+  id-token: write
 
 jobs:
   github-release:
@@ -29,17 +30,14 @@ jobs:
     steps:
       - name: Checkout
         uses: actions/checkout@v4
+        with:
+          persist-credentials: false
 
       - name: Set up Ruby
         uses: ruby/setup-ruby@v1
         with:
           ruby-version: '3.0.0'
           bundler-cache: true
 
-      - name: Build gem
-        run: gem build invoicetronic_sdk.gemspec
-
       - name: Publish to RubyGems
         uses: rubygems/release-gem@v1
-        with:
-          gem-name: invoicetronic_sdk