public InlongGroupInfo getGroupIfExists(String inlongGroupId) {
        if (this.isGroupExists(inlongGroupId)) {
            return getGroupInfo(inlongGroupId);
        }
        return null;
    }
Get inlong group by the given inlong group id.

@param inlongGroupId the given inlong group id
@return inlong group info if exists, null will be returned if not exits
inlong-manager/manager-client/src/main/java/org/apache/inlong/manager/client/api/inner/client/InlongGroupClient.java