test_runner: fix env option validation

[hanityx]

Invalid values passed to run({ env }) currently throw
ERR_INTERNAL_ASSERTION because the option name is missing from the
validateObject() call.

This passes options.env to the validator so callers receive
ERR_INVALID_ARG_TYPE instead, and adds a regression test for invalid
values.

Tests: tools/test.py test/parallel/test-runner-run.mjs

[nodejs-github-bot]

Review requested:

• @nodejs/test_runner

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 90.15%. Comparing base (bec3d0b) to head (22990d1).
⚠️ Report is 96 commits behind head on main.

Additional details and impacted files

@@           Coverage Diff           @@
##             main   #64865   +/-   ##
=======================================
  Coverage   90.14%   90.15%           
=======================================
  Files         746      746           
  Lines      242763   242763           
  Branches    45761    45762    +1     
=======================================
+ Hits       218848   218867   +19     
+ Misses      15402    15393    -9     
+ Partials     8513     8503   -10     

Files with missing lines	Coverage Δ
lib/internal/test_runner/runner.js	94.42% <100.00%> (ø)

... and 29 files with indirect coverage changes

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[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/75424/

[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/75441/

[nodejs-github-bot]

Landed in 8465148