message: Warning message if no executable target is found
diff: @@ -694,6 +694,12 @@ export class CMakeTools implements vscode.Disposable, api.CMakeToolsAPI {
  const target_name = this._stateManager.launchTargetName;
  const chosen = (await this.executableTargets).find(e => e.name == target_name);
  if (!chosen) {
  + log.showChannel();
  + log.warning('=======================================================');
  + log.warning('No executable target was found to launch. Please check:');
  + log.warning(' - Have you called add_executable() in your CMake project?');
  + log.warning(' - Have you executed a successful CMake configure? ');
  + log.warning('No program will be executed');
  return null;
  }
  return chosen.path;
  