Enable funlen linter (part 5)

[brojeg]

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Pull request type

Please check the type of change your PR introduces:

• Bugfix
• Feature
• Code style update (formatting, renaming)
• Refactoring (no functional changes, no api changes)
• Build related changes
• Documentation content changes
• Other (please describe):

What is the current behavior?

Issue Number: 934

What is the new behavior?

Other information

[codecov-commenter]

Codecov Report

Attention: Patch coverage is 73.77049% with 16 lines in your changes are missing coverage. Please review.

Project coverage is 41.09%. Comparing base (b7a9b51) to head (71ed802).
Report is 128 commits behind head on master.

Files	Patch %	Lines
internal/pool/pool.go	76.27%	12 Missing and 2 partials ⚠️
log/driver.go	0.00%	1 Missing ⚠️
log/topic.go	0.00%	1 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #1232      +/-   ##
==========================================
+ Coverage   40.80%   41.09%   +0.29%     
==========================================
  Files         309      312       +3     
  Lines       32747    33220     +473     
==========================================
+ Hits        13361    13651     +290     
- Misses      18959    19108     +149     
- Partials      427      461      +34     

Flag	Coverage Δ
go-1.21.x	43.23% <73.77%> (+0.29%)	⬆️
go-1.22.x	41.08% <73.77%> (+0.29%)	⬆️
macOS	40.57% <72.54%> (+0.27%)	⬆️
ubuntu	40.55% <72.54%> (+0.25%)	⬆️
unit	41.09% <73.77%> (+0.29%)	⬆️
windows	41.07% <73.77%> (+0.28%)	⬆️

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[rekby]

Please don't remove empty lines.

They separate the code into logical blocks for better readability.