The length of jfs_chunk slices is greater than 24

[fengjiannan2010]

What happened:The length of jfs_chunk slices is greater than 24

What you expected to happen:I'm not sure if this is correct

How to reproduce it (as minimally and precisely as possible):Use the V1.0.4 code to run in goland debug mode, and make a breakpoint in the Write method in sql.go

Environment:

• JuiceFS version (use juicefs --version) :V1.0.4
• OS (e.g cat /etc/os-release):
  PRETTY_NAME="Ubuntu 22.04.3 LTS"
  NAME="Ubuntu"
  VERSION_ID="22.04"
  VERSION="22.04.3 LTS (Jammy Jellyfish)"
  VERSION_CODENAME=jammy
  ID=ubuntu
  ID_LIKE=debian
  HOME_URL="https://www.ubuntu.com/"
  SUPPORT_URL="https://help.ubuntu.com/"
  BUG_REPORT_URL="https://bugs.launchpad.net/ubuntu/"
  PRIVACY_POLICY_URL="https://www.ubuntu.com/legal/terms-and-policies/privacy-policy"
  UBUNTU_CODENAME=jammy
• Kernel (e.g. uname -a):
  Linux netzon-base 6.2.0-26-generic Use Github Actions instead of Travis for CI/CD. #26~22.04.1-Ubuntu SMP PREEMPT_DYNAMIC Thu Jul 13 16:27:29 UTC 2 x86_64 x86_64 x86_64 GNU/Linux
• Metadata engine info (version, cloud provider managed or self maintained): PostgreSQL Version:(PostgreSQL) 15.3 (Debian 15.3-1.pgdg110+1)

added log output as below：

[SandyXSD]

A chunk may contain multiple slices, thus it's size being N * 24 bytes.

[SandyXSD]

From the internals doc:

Slices are an array of bytes, and each Slice corresponds to 24 bytes.