remove set-env in CI

.github/workflows/vsenv.bat

@@ -12,6 +12,6 @@ for /f "usebackq delims=*" %%i in (`%VSWHERE% -latest -property installationPath
 :: See: https://stackoverflow.com/questions/39183272/loop-through-all-environmental-variables-and-take-actions-depending-on-prefix
 setlocal
 for /f "delims== tokens=1,2" %%a in ('set') do (
-  echo ::set-env name=%%a::%%b
+  echo %%a=%%b >> $GITHUB_ENV
 )
-endlocal
+endlocal