[Feature] Add HRFormer backbone

[RockeyCoss]

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Motivation

Add HRFormer backbone

Modification

Add HRFormer backbone

[codecov[bot]]

Codecov Report

Merging #1382 (bcccf35) into master (2d8be37) will increase coverage by 0.34%. The diff coverage is 99.50%.

@@            Coverage Diff             @@
##           master    #1382      +/-   ##
==========================================
+ Coverage   90.40%   90.74%   +0.34%     
==========================================
  Files         141      142       +1     
  Lines        8443     8646     +203     
  Branches     1423     1448      +25     
==========================================
+ Hits         7633     7846     +213     
+ Misses        572      565       -7     
+ Partials      238      235       -3     

Flag	Coverage Δ
unittests	90.74% <99.50%> (+0.34%)	:arrow_up:

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

Impacted Files	Coverage Δ
mmseg/models/backbones/hrformer.py	99.50% <99.50%> (ø)
mmseg/models/backbones/__init__.py	100.00% <100.00%> (ø)
mmseg/models/backbones/hrnet.py	88.75% <0.00%> (+4.26%)	:arrow_up:

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[lorinczszabolcs]

Hi!

Any updates on this? :) Thanks in advance!