fix: output_bytes metric in hash aggregation

[ariel-miculas]

Which issue does this PR close?

• Closes Incorrect output_bytes metric in hash aggregation #23776.

Rationale for this change

Summing together the produced sliced RecordBatches in hash aggregation leads to inflated output_bytes metric

What changes are included in this PR?

Are these changes tested?

Yes

Are there any user-facing changes?

If the metrics are user-facing, then yes.

[codecov-commenter]

Codecov Report

❌ Patch coverage is 85.92965% with 28 lines in your changes missing coverage. Please review.
✅ Project coverage is 80.71%. Comparing base (eef1017) to head (ab748ff).
⚠️ Report is 10 commits behind head on main.

Files with missing lines	Patch %	Lines
...fusion/physical-plan/src/aggregates/hash_stream.rs	81.20%	7 Missing and 21 partials ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #23777      +/-   ##
==========================================
- Coverage   80.71%   80.71%   -0.01%     
==========================================
  Files        1089     1089              
  Lines      368748   368928     +180     
  Branches   368748   368928     +180     
==========================================
+ Hits       297633   297771     +138     
- Misses      53372    53390      +18     
- Partials    17743    17767      +24     

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[Jithendra2608]

Hi @ariel-miculas! I was taking a look at the failing CI checks to see if I could help unblock this.
It looks like the typos job is failing because of a small spelling error in datafusion/physical-expr-common/src/metrics/baseline.rs on line 326 (accross instead of across).

Fixing that one word should turn the CI green. Hope this helps, and great work on the hash aggregation metrics!

[ariel-miculas]

@2010YOUY01 coud you please take a look?