add automatic changelog generation step (#639)

.github/workflows/release.yml

@@ -472,16 +472,28 @@ jobs:
             arduino-create-agent-windows-2019-386/arduino-create-agent.exe
             arduino-create-agent-windows-2019-amd64/arduino-create-agent.exe
 
+      - name: Create changelog
+        uses: arduino/create-changelog@v1
+        with:
+          tag-regex: '^[0-9]+\.[0-9]+\.[0-9]+.*$'
+          filter-regex: '^\[(skip|changelog)[ ,-](skip|changelog)\].*'
+          case-insensitive-regex: true
+          changelog-file-path: "CHANGELOG.md"
+
       - name: Organize release body message #use sed to clean and format the output markdown style
         id: release_body
         run: |
+          body=$(cat CHANGELOG.md)
+          body="${body//'%'/'%25'}"
+          body="${body//$'\n'/'%0A'}"
+          body="${body//$'\r'/'%0D'}"
           vt_title_pre="<details close>\n<summary>VirusTotal analysis 🛡</summary>\n\n"
           vt_links="$(echo ${{ steps.virustotal_step.outputs.analysis}} | sed 's/release\///g' | sed 's/,/\n/g' | sed 's/^/- [/' | sed 's/=/](/' | sed 's/$/)/')"
           vt_title_post="\n</details>"
           vt_title_pre="${vt_title_pre//'\n'/'%0A'}"
           vt_links="${vt_links//$'\n'/'%0A'}" # replace \n with a special character -> generates a single lines, \n will be reintroduced later
           vt_title_post="${vt_title_post//'\n'/'%0A'}"
-          echo "::set-output name=RBODY::$vt_title_pre$vt_links$vt_title_post"
+          echo "::set-output name=RBODY::$body'%0A'$vt_title_pre$vt_links$vt_title_post"
 
       - name: Create Github Release
         uses: actions/create-release@v1