optimize: delete useless code

[Stevent-fei]

Describe what this PR does / why we need it

delete useless code of build and pkg module

Does this pull request fix one issue?

Describe how you did it

Describe how to verify it

Special notes for reviews

[codecov-commenter]

Codecov Report

Base: 18.64% // Head: 19.45% // Increases project coverage by +0.81% 🎉

Coverage data is based on head (590883b) compared to base (af34af6).
Patch has no changes to coverable lines.

❗ Current head 590883b differs from pull request most recent head 3336b6d. Consider uploading reports for the commit 3336b6d to get more accurate results

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Additional details and impacted files

@@            Coverage Diff             @@
##             main    #2058      +/-   ##
==========================================
+ Coverage   18.64%   19.45%   +0.81%     
==========================================
  Files          99       96       -3     
  Lines        9179     8785     -394     
==========================================
- Hits         1711     1709       -2     
+ Misses       7243     6853     -390     
+ Partials      225      223       -2     

Impacted Files	Coverage Δ
build/layerutils/manifests/manifests.go	0.00% <ø> (ø)
pkg/config/config.go	27.95% <ø> (ø)
build/buildimage/differ.go
build/buildimage/middleware.go
build/buildimage/utils.go

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[kakaZhou719]

LGTM