support the compile on linux system, like ubuntu and centos

[alonlong]

the test is passed on ubuntu and centos, and the main dependent library is unwind:

1. for ubuntu: sudo apt-get install libunwind libunwind-dev
2. for centos: sudo dnf install libunwind libunwind-devel

[codecov]

Codecov Report

Merging #202 (6799100) into main (bc5d5e7) will increase coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##             main     #202      +/-   ##
==========================================
+ Coverage   57.21%   57.23%   +0.02%     
==========================================
  Files          73       73              
  Lines        2942     2943       +1     
==========================================
+ Hits         1683     1684       +1     
  Misses       1114     1114              
  Partials      145      145              

Impacted Files	Coverage Δ
pkg/agent/session.go	63.94% <0.00%> (ø)
pkg/agent/spy/spy.go	5.00% <0.00%> (ø)
pkg/analytics/analytics.go	84.06% <0.00%> (+0.24%)	⬆️

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