[dask] Random forest estimators

[trivialfis]

No description provided.

[codecov-io]

Codecov Report

Merging #6602 (559f0bd) into master (0027220) will increase coverage by 0.20%.
The diff coverage is 100.00%.

@@            Coverage Diff             @@
##           master    #6602      +/-   ##
==========================================
+ Coverage   80.38%   80.59%   +0.20%     
==========================================
  Files          13       13              
  Lines        3656     3679      +23     
==========================================
+ Hits         2939     2965      +26     
+ Misses        717      714       -3     

Impacted Files	Coverage Δ
python-package/xgboost/sklearn.py	89.61% <ø> (ø)
python-package/xgboost/dask.py	82.18% <100.00%> (+0.66%)	⬆️
python-package/xgboost/tracker.py	95.11% <0.00%> (+1.12%)	⬆️

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