LU-17362 build: Update ZFS version to 2.1.15

LU-17362 build: Update ZFS version to 2.1.15

Update ZFS version to 2.1.15. The changes are listed in:
https://github.com/openzfs/zfs/releases/tag/zfs-2.1.15

Lustre-change: https://review.whamcloud.com/54769
Lustre-commit: 01103eba35e88638d8860457fbdf89b101d4ab67

Test-Parameters: trivial fstype=zfs mdtcount=4 mdscount=2 \
  clientdistro=el8.9 serverdistro=el8.9 testlist=sanity

Test-Parameters: optional fstype=zfs mdtcount=4 mdscount=2 \
  testgroup=full-dne-zfs-part-1

Test-Parameters: optional fstype=zfs mdtcount=4 mdscount=2 \
  testgroup=full-dne-zfs-part-2

Test-Parameters: optional fstype=zfs mdtcount=4 mdscount=2 \
  testgroup=full-dne-zfs-part-3

Change-Id: I51532dbf9dbcadf64bb9dbd3b10e88d0cab38ffd
Signed-off-by: Jian Yu <yujian@whamcloud.com>
Reviewed-on: https://review.whamcloud.com/c/fs/lustre-release/+/54791
Tested-by: jenkins <devops@whamcloud.com>
Tested-by: Maloo <maloo@whamcloud.com>
Reviewed-by: Alex Zhuravlev <bzzz@whamcloud.com>
Reviewed-by: Olaf Faaland <faaland1@llnl.gov>
Reviewed-by: Oleg Drokin <green@whamcloud.com>