process: stop _kill on missing arguments

[Archkon]

Return immediately after throwing ERR_MISSING_ARGS so process._kill() does not coerce missing arguments or call uv_kill().

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.30%. Comparing base (c18fd90) to head (c74b5da).
⚠️ Report is 11 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #65072      +/-   ##
==========================================
- Coverage   90.31%   90.30%   -0.01%     
==========================================
  Files         759      759              
  Lines      247646   247647       +1     
  Branches    46697    46703       +6     
==========================================
- Hits       223654   223642      -12     
- Misses      15463    15469       +6     
- Partials     8529     8536       +7     

Files with missing lines	Coverage Δ
src/node_process_methods.cc	88.93% <100.00%> (+0.40%)	⬆️

... and 27 files with indirect coverage changes

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