chore: cache space reservation when sorting is enabled

[dkharms]

Description

Previous version substracted cache size even if we skip documents sorting.

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[codecov-commenter]

Codecov Report

❌ Patch coverage is 62.50000% with 3 lines in your changes missing coverage. Please review.
✅ Project coverage is 71.17%. Comparing base (8cf7b08) to head (69e2c47).

Files with missing lines	Patch %	Lines
fracmanager/config.go	62.50%	3 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff           @@
##             main     #480   +/-   ##
=======================================
  Coverage   71.16%   71.17%           
=======================================
  Files         232      232           
  Lines       18466    18467    +1     
=======================================
+ Hits        13142    13143    +1     
+ Misses       4341     4340    -1     
- Partials      983      984    +1     

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[github-actions]

🔴 Performance Degradation

Some benchmarks have degraded compared to the previous run.
Click on Show table button to see full list of degraded benchmarks.

Show table

Name	Previous	Current	Ratio	Verdict
Block_Unpack-4	8cf7b0	ae8a2c
	91216.00 ns/op	101760.00 ns/op	1.12	🔴
ProcessDocuments-4	8cf7b0	ae8a2c
	508.00 B/op	13673.00 B/op	26.92	🔴