LU-18193 test: fix sanity 300l

LU-18193 test: fix sanity 300l

Sanity.sh test_300l mkdir with non-root user, but it's creating a
remote dir, it will fail because it requires enable_remote_dir_gid=-1.

Fixes: 29d18f84e ("LU-6341 llite: Use ll_dir_getstripe to get default LMVEA")
Test-Parameters: trivial testlist=sanity env=ONLY=300l,ONLY_REPEAT=30
Signed-off-by: Lai Siyao <lai.siyao@whamcloud.com>
Change-Id: I03d61e89396b205d80ed302b2fd6ccf716a39366
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/56252
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Alex Zhuravlev <bzzz@whamcloud.com>
Reviewed-by: Andreas Dilger <adilger@whamcloud.com>
Reviewed-by: Oleg Drokin <green@whamcloud.com>