fix: return explicit null result for shutdown response#20

CppCXY merged 1 commit intoCppCXY:mainCppCXY/LanguageServer.Framework:mainfrom

r-koubou:fix/invalid-response-when-shutdown-request-from-clientr-koubou/LanguageServer.Framework:fix/invalid-response-when-shutdown-request-from-clientCopy head branch name to clipboard