Add JET tests, and fix some existing JET problems

[DilumAluthge]

No description provided.

[codecov]

Codecov Report

❌ Patch coverage is 0% with 4 lines in your changes missing coverage. Please review.
✅ Project coverage is 1.03%. Comparing base (11d491c) to head (41ff63a).
⚠️ Report is 1 commits behind head on master.

Files with missing lines	Patch %	Lines
src/slurmmanager.jl	0.00%	4 Missing ⚠️

❗ There is a different number of reports uploaded between BASE (11d491c) and HEAD (41ff63a). Click for more details.

HEAD has 2 uploads less than BASE

Flag	BASE (11d491c)	HEAD (41ff63a)
	4	2

Additional details and impacted files

@@            Coverage Diff             @@
##           master     #85       +/-   ##
==========================================
- Coverage   93.61%   1.03%   -92.59%     
==========================================
  Files           2       2               
  Lines          94      97        +3     
==========================================
- Hits           88       1       -87     
- Misses          6      96       +90     

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[DilumAluthge]

Closing in favor of #86