feat: introduce percentile aggregator for window sliding

[cheney-lin]

What type of PR is this?

Features

What this PR does / why we need it:

Which issue(s) this PR fixes:

Special notes for your reviewer:

[codecov]

Codecov Report

Patch coverage: 79.45% and project coverage change: +0.62% 🎉

Comparison is base (c8b2187) 50.20% compared to head (29e3959) 50.82%.

Additional details and impacted files

@@            Coverage Diff             @@
##             main     #164      +/-   ##
==========================================
+ Coverage   50.20%   50.82%   +0.62%     
==========================================
  Files         408      408              
  Lines       38774    38844      +70     
==========================================
+ Hits        19467    19744     +277     
+ Misses      17126    16882     -244     
- Partials     2181     2218      +37     

Flag	Coverage Δ
unittest	50.82% <79.45%> (+0.62%)	⬆️

Flags with carried forward coverage won't be shown. Click here to find out more.

Files Changed	Coverage Δ
.../sysadvisor/qosaware/reporter/headroom_reporter.go	100.00% <ø> (ø)
.../sysadvisor/qosaware/reporter/headroom_reporter.go	67.27% <55.55%> (-3.57%)	⬇️
pkg/util/general/window.go	89.31% <80.70%> (-6.64%)	⬇️
...r/plugin/qosaware/reporter/manager/resource/cpu.go	100.00% <100.00%> (ø)
...ugin/qosaware/reporter/manager/resource/generic.go	100.00% <100.00%> (ø)
...lugin/qosaware/reporter/manager/resource/memory.go	100.00% <100.00%> (ø)

... and 22 files with indirect coverage changes

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