Use MMCV's EvalHook in MMDetection

[hhaAndroid]

refer: open-mmlab/mmcv#739

[ZwwWayne]

1. CI failed.
2. Need to keep the module in mmdet.core for at least a month and add warnings to avoid BC-breaking.

[codecov]

Codecov Report

Merging #4806 (b66fee2) into master (c6515a7) will increase coverage by 0.09%.
The diff coverage is 83.33%.

❗ Current head b66fee2 differs from pull request most recent head 5067930. Consider uploading reports for the commit 5067930 to get more accurate results

@@            Coverage Diff             @@
##           master    #4806      +/-   ##
==========================================
+ Coverage   65.17%   65.27%   +0.09%     
==========================================
  Files         269      269              
  Lines       20844    20733     -111     
  Branches     3500     3469      -31     
==========================================
- Hits        13586    13534      -52     
+ Misses       6492     6440      -52     
+ Partials      766      759       -7     

Flag	Coverage Δ
unittests	65.24% <83.33%> (+0.09%)	⬆️

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Impacted Files	Coverage Δ
mmdet/core/evaluation/eval_hooks.py	72.22% <83.33%> (+20.52%)	⬆️
mmdet/utils/logger.py	60.00% <0.00%> (-40.00%)	⬇️

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