[Feature]Add Minkowski block

[sunjiahao1999]

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Motivation

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Modification

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BC-breaking (Optional)

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Checklist

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[codecov]

Codecov Report

Patch coverage: 43.47% and project coverage change: -0.01 ⚠️

Comparison is base (65e2832) 46.93% compared to head (ef58b68) 46.92%.

❗ Current head ef58b68 differs from pull request most recent head aa40613. Consider uploading reports for the commit aa40613 to get more accurate results

Additional details and impacted files

@@             Coverage Diff             @@
##           dev-1.x    #2528      +/-   ##
===========================================
- Coverage    46.93%   46.92%   -0.01%     
===========================================
  Files          276      277       +1     
  Lines        23189    23235      +46     
  Branches      3619     3622       +3     
===========================================
+ Hits         10883    10903      +20     
- Misses       11615    11641      +26     
  Partials       691      691              

Flag	Coverage Δ
unittests	46.92% <43.47%> (-0.01%)	⬇️

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Impacted Files	Coverage Δ
mmdet3d/models/layers/minkowski_engine_block.py	42.22% <42.22%> (ø)
mmdet3d/models/layers/__init__.py	100.00% <100.00%> (ø)

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[Xiangxu-0103]

We may also need to update mmdet3d/models/layers/__init__.py