[improve][docbot] Move the preceding steps into the action (#68) * Move the preceding steps into the action Signed-off-by: Max Xu <maxs.xu@gmail.com> * Fix typo Signed-off-by: Max Xu <maxs.xu@gmail.com> * Remove unnecessary ref The ref uses the default branch. Signed-off-by: Max Xu <maxs.xu@gmail.com> Signed-off-by: Max Xu <maxs.xu@gmail.com>