fix: Add default values for columnAlignmentMap in hydrate/dehydrate methods

[gzh2003]

For DH-10205. The current implementation breaks enterprise code that uses hydration/dehydration without providing a columnAlignmentMap (such as QueryMonitorGridPanel).

We could update the few places that call hydrate/dehydrate iris grid when updating packages in DHE. But it is probably better to set defaults as Matt suggested.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 2 lines in your changes missing coverage. Please review.
✅ Project coverage is 44.61%. Comparing base (eca54ca) to head (ae1869d).
⚠️ Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
packages/iris-grid/src/IrisGridUtils.ts	0.00%	2 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2518      +/-   ##
==========================================
+ Coverage   44.59%   44.61%   +0.01%     
==========================================
  Files         764      764              
  Lines       42778    42800      +22     
  Branches    10962    10766     -196     
==========================================
+ Hits        19078    19096      +18     
- Misses      23641    23693      +52     
+ Partials       59       11      -48     

Flag	Coverage Δ
unit	44.61% <0.00%> (+0.01%)	⬆️

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