lib: avoid event override by assignment

[erights]

See #43907

[ljharb]

With this last comment, and with some tests (that install an inherited setter and verify it's not called, and then remove the setter, presumably) this PR LGTM

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.86%. Comparing base (db18bc8) to head (f1958ee).

Additional details and impacted files

@@ Coverage Diff @@## main #58315 +/- ## ========================================== - Coverage 89.87% 89.86% -0.01%  ========================================== Files 656 656 Lines 192956 192993 +37 Branches 37846 37842 -4 ========================================== + Hits 173411 173429 +18 - Misses 12103 12110 +7 - Partials 7442 7454 +12 

Files with missing lines	Coverage Δ
lib/events.js	99.84% <100.00%> (+0.25%)	⬆️

... and 26 files with indirect coverage changes

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