fix: test failure in test_fsl_packed_struct

[broccoliSpicy]

The current main has test failure in test_fsl_packed_struct because I introduced statistics gathering for StructDataBlock, but not statistics gathering in FixedSizeListDataBlock.

To fix this test, I can add statistics gathering(in this case, only Stat::MaxLength is needed) for FixedSizeListDataBlock.

I think the variants of FixedSizeList's child datablock can only be either fixed width datablock or another fixed size list?

This PR however only disables the packed struct encoding test for fixed size list.

---

after reading https://docs.rs/arrow-array/53.3.0/src/arrow_array/array/fixed_size_list_array.rs.html#133, it looks like that the child of a fixed size list can be any array type, which means to support MaxLength statistics for fixed size list data block, we need to have MaxLength statistics for all other datablock types.

[github-actions]

ACTION NEEDED
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[westonpace]

Code looks fine but fix conventional commits CI failure

[codecov-commenter]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 78.48%. Comparing base (ef9d0c2) to head (376928f).
Report is 1 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #3227      +/-   ##
==========================================
+ Coverage   78.45%   78.48%   +0.03%     
==========================================
  Files         244      245       +1     
  Lines       84554    84815     +261     
  Branches    84554    84815     +261     
==========================================
+ Hits        66333    66564     +231     
- Misses      15418    15439      +21     
- Partials     2803     2812       +9     

Flag	Coverage Δ
unittests	78.48% <ø> (+0.03%)	⬆️

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