Always test that the current typechecker can type check the standard library of rascal

[DavyLandman]

It reuses most of the code inside the maven runner, to make sure we're hitting the same execution path (and parallel behavior).

[codecov]

Codecov Report

❌ Patch coverage is 0% with 17 lines in your changes missing coverage. Please review.
✅ Project coverage is 46%. Comparing base (8f12439) to head (e9eeb56).
⚠️ Report is 3 commits behind head on main.

Files with missing lines	Patch %	Lines
src/org/rascalmpl/shell/RascalCompile.java	0%	10 Missing ⚠️
...c/org/rascalmpl/shell/AbstractCommandlineTool.java	0%	6 Missing ⚠️
src/org/rascalmpl/library/util/PathConfig.java	0%	1 Missing ⚠️

Additional details and impacted files

@@           Coverage Diff            @@
##              main   #2542    +/-   ##
========================================
- Coverage       47%     46%    -1%     
+ Complexity    6714    6625    -89     
========================================
  Files          792     792            
  Lines        65342   65350     +8     
  Branches      9784    9784            
========================================
- Hits         30938   30478   -460     
- Misses       31984   32521   +537     
+ Partials      2420    2351    -69     

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