update nms config in demo/faster_rcnn

[wangruohui]

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Motivation

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Modification

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[codecov]

Codecov Report

Merging #899 (3e5b432) into master (529f454) will decrease coverage by 0.02%.
The diff coverage is n/a.

@@            Coverage Diff             @@
##           master     #899      +/-   ##
==========================================
- Coverage   83.62%   83.60%   -0.03%     
==========================================
  Files         132      132              
  Lines        9966     9966              
  Branches     1718     1718              
==========================================
- Hits         8334     8332       -2     
- Misses       1215     1217       +2     
  Partials      417      417              

Flag	Coverage Δ
unittests	83.60% <ø> (-0.02%)	⬇️

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Impacted Files	Coverage Δ
mmaction/datasets/pipelines/augmentations.py	92.98% <0.00%> (-0.46%)	⬇️
mmaction/core/evaluation/accuracy.py	93.18% <0.00%> (+0.90%)	⬆️

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