feat(progress): progress uses n as CSS vars prefix

[XieZongChen]

close #1929
ref #1842

[vercel]

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[codecov]

Codecov Report

Merging #1930 (bb00f49) into main (ba93e0b) will not change coverage.
The diff coverage is n/a.

@@           Coverage Diff           @@
##             main    #1930   +/-   ##
=======================================
  Coverage   64.62%   64.62%           
=======================================
  Files         890      890           
  Lines       17404    17404           
  Branches     4127     4127           
=======================================
  Hits        11248    11248           
  Misses       5377     5377           
  Partials      779      779           

Impacted Files	Coverage Δ
src/progress/src/Progress.tsx	91.66% <ø> (ø)
src/progress/src/styles/index.cssr.ts	100.00% <ø> (ø)

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