add MatMiner datasets

[CarloLucibello]

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[codecov-commenter]

Codecov Report

Attention: Patch coverage is 5.55556% with 34 lines in your changes missing coverage. Please review.

Project coverage is 35.80%. Comparing base (e86b1ce) to head (546eb58).
Report is 59 commits behind head on master.

Files with missing lines	Patch %	Lines
src/datasets/misc/matminer.jl	2.85%	34 Missing ⚠️

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #181      +/-   ##
==========================================
- Coverage   36.29%   35.80%   -0.49%     
==========================================
  Files          43       44       +1     
  Lines        2240     2276      +36     
==========================================
+ Hits          813      815       +2     
- Misses       1427     1461      +34     

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