Revert "Disable tests against Optim temporarily"

[devmotion]

Reverts #407

I just came across #407. It seems that Optim CI was updated and fixed recently.

[codecov]

Codecov Report

All modified and coverable lines are covered by tests ✅

Project coverage is 0.00%. Comparing base (877375f) to head (abbbf3f).
Report is 2 commits behind head on master.

❗ There is a different number of reports uploaded between BASE (877375f) and HEAD (abbbf3f). Click for more details.

HEAD has 8 uploads less than BASE

Flag	BASE (877375f)	HEAD (abbbf3f)
	18	10

Additional details and impacted files

@@            Coverage Diff             @@
##           master    #409       +/-   ##
==========================================
- Coverage   99.48%   0.00%   -99.49%     
==========================================
  Files           8       8               
  Lines        1157    1155        -2     
==========================================
- Hits         1151       0     -1151     
- Misses          6    1155     +1149     

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[jishnub]

Looks like Distributions is broken now

[devmotion]

Yes, that's a known issue of the master branch. I had opened a PR but your PR seemed a bit better, thanks!