Upload on Tag workflow: allow empty change log for version missing in…

… Readme's Change Log

.github/workflows/upload-on-tag.yaml

@@ -38,7 +38,9 @@ jobs:
         print(f'===> Version:{version}')
         pattern = rf'## Change log.*### Version {version}\s*(.*?)\s*(\n(### Version)|(\[\d+\]:)|$)'
         fileContent = open('readme.md', 'r', encoding='utf8').read()
-        changeLog = re.search(pattern, fileContent, re.DOTALL).group(1) + '\n'
+        match = re.search(pattern, fileContent, re.DOTALL)
+        changeLog = match.group(1) if match else ""
+        changeLog += '\n'
         print(f'===> ChangeLog:\n<<<{changeLog}>>>\n')
         open('changelog.md', 'w', encoding='utf-8').write(changeLog)
       shell: python