CASMPET-7209 add instructions to mount admin-tools bucket if desired

[leliasen-hpe]

Description

In CSM 1.2 and CSM 1.3, the admin-tools s3 bucket was mounted. In CSM 1.4+, this bucket is no longer mounted. This PR updates documentation so that the admin-tools bucket can be manually mounted if desired.

Tested 3 different test cases.

1. Admin-tools bucket was not mounted and no entry was in /etc/fstab.

   Configuring for admin-tools S3 bucket at /var/lib/admin-tools for admin-tools S3 user
   Mounting bucket: admin-tools at /var/lib/admin-tools
   Adding fstab entry for admin-tools S3 bucket at /var/lib/admin-tools for admin-tools S3 user
   Set cache pruning for admin-tools to 5G of the 200G volume (every 2nd hour)
   Done mounting admin-tools S3 bucket
   
   /etc/fstab has the following content:
   sds /var/opt/cray/sdu/collection-mount fuse.s3fs _netdev,allow_other,passwd_file=/root/.sds.s3fs,url=http://rgw-vip.nmn,use_path_request_style,use_cache=/var/lib/s3fs_cache,check_cache_dir_exist,use_xattr,uid=2370,gid=2370,umask=0007,allow_other 0 0
   config-data /var/opt/cray/config-data fuse.s3fs _netdev,allow_other,passwd_file=/root/.config-data.s3fs,url=http://rgw-vip.nmn,use_path_request_style,use_xattr 0 0
   admin-tools /var/lib/admin-tools fuse.s3fs _netdev,allow_other,passwd_file=/root/.admin-tools.s3fs,url=http://rgw-vip.nmn,use_path_request_style,use_cache=/var/lib/s3fs_cache,check_cache_dir_exist,use_xattr 0 0
   admin-tools was successfully added to /etc/fstab
   
   The following s3fs mounts exist:
   s3fs on /var/opt/cray/sdu/collection-mount type fuse.s3fs (rw,nosuid,nodev,relatime,user_id=0,group_id=0,allow_other)
   s3fs on /var/opt/cray/config-data type fuse.s3fs (rw,nosuid,nodev,relatime,user_id=0,group_id=0)
   s3fs on /var/lib/admin-tools type fuse.s3fs (rw,nosuid,nodev,relatime,user_id=0,group_id=0)
   /var/lib/admin-tools is an s3fs mount
   
   Successfully mounted admin-tools bucket

2. Admin-tools bucket was already mounted

   ncn-m001:~/leliasen # ./mount-admin-tools-bucket.sh
   Configuring for admin-tools S3 bucket at /var/lib/admin-tools for admin-tools S3 user
   Mounting bucket: admin-tools at /var/lib/admin-tools
   s3fs: MOUNTPOINT directory /var/lib/admin-tools is not empty. if you are sure this is safe, can use the 'nonempty' mount option.
   Error: Check that admin-tools is not already mounted and /var/lib/admin-tools is empty.
   ncn-m001:~/leliasen # echo $?
   1

3. Admin-tools bucket was not mounted but and entry already existed in /etc/fstab

   ncn-m001:~/leliasen # ./mount-admin-tools-bucket.sh
   Configuring for admin-tools S3 bucket at /var/lib/admin-tools for admin-tools S3 user
   Mounting bucket: admin-tools at /var/lib/admin-tools
   Adding fstab entry for admin-tools S3 bucket at /var/lib/admin-tools for admin-tools S3 user
   An entry in /etc/fstab already exists for admin-tools /var/lib/admin-tools fuse.s3fs
   Set cache pruning for admin-tools to 5G of the 200G volume (every 2nd hour)
   Done mounting admin-tools S3 bucket
   
   /etc/fstab has the following content:
   sds /var/opt/cray/sdu/collection-mount fuse.s3fs _netdev,allow_other,passwd_file=/root/.sds.s3fs,url=http://rgw-vip.nmn,use_path_request_style,use_cache=/var/lib/s3fs_cache,check_cache_dir_exist,use_xattr,uid=2370,gid=2370,umask=0007,allow_other 0 0
   config-data /var/opt/cray/config-data fuse.s3fs _netdev,allow_other,passwd_file=/root/.config-data.s3fs,url=http://rgw-vip.nmn,use_path_request_style,use_xattr 0 0
   admin-tools /var/lib/admin-tools fuse.s3fs _netdev,allow_other,passwd_file=/root/.admin-tools.s3fs,url=http://rgw-vip.nmn,use_path_request_style,use_cache=/var/lib/s3fs_cache,check_cache_dir_exist,use_xattr 0 0
   admin-tools was successfully added to /etc/fstab
   
   The following s3fs mounts exist:
   s3fs on /var/opt/cray/sdu/collection-mount type fuse.s3fs (rw,nosuid,nodev,relatime,user_id=0,group_id=0,allow_other)
   s3fs on /var/opt/cray/config-data type fuse.s3fs (rw,nosuid,nodev,relatime,user_id=0,group_id=0)
   s3fs on /var/lib/admin-tools type fuse.s3fs (rw,nosuid,nodev,relatime,user_id=0,group_id=0)
   /var/lib/admin-tools is an s3fs mount
   
   Successfully mounted admin-tools bucket

Checklist

• If I added any command snippets, the steps they belong to follow the prompt conventions (see example).
• If I added a new directory, I also updated .github/CODEOWNERS with the corresponding team in Cray-HPE.
• My commits or Pull-Request Title contain my JIRA information, or I do not have a JIRA.

[leliasen-hpe]

/backport release/1.5

[leliasen-hpe]

/backport release/1.4

[github-actions]

Backporting into branch release/1.5 was successful. New PR: #5320

[github-actions]

Backporting into branch release/1.4 was successful. New PR: #5321

[rustydb]

Left some feedback from nits to defensive programming enhancements.

[rustydb]

Just shfmt and shellcheck need work and then we can backport to 1.5 and 1.4.

[leliasen-hpe]

/backport release/1.5

[github-actions]

Backporting into branch release/1.5 was successful. New PR: #5355

[leliasen-hpe]

/backport release/1.4

[github-actions]

Backporting into branch release/1.4 was successful. New PR: #5356