git-cli doesn't support http connection timeout, so we cannot set short 30s connection timeout on git fetch. We don't want to put operation timeout that short because intial `git clone` can take pretty long. go-git does expose http client but only globally and is less efficient than cli. So as a hack, just fetch remote server to check if knot is available and is valid git remote server Signed-off-by: Seongmin Lee <git@boltless.me>