ffi: prevent premature GC of DynamicLibrary

[semimikoh]

Fixes: #63010

Functions created by getFunction() do not hold a strong reference
to the owning DynamicLibrary. V8 may garbage-collect the library
while derived functions are still in use, causing spurious
ERR_FFI_LIBRARY_CLOSED errors in tight loops.

Store a Global<Object> reference to the library in
FFIFunctionInfo so the library remains alive as long as any
derived function exists. The reference is released when the
function is garbage-collected via CleanupFunctionInfo.

Verification

$ # reproduce issue #63010 with the test script from the report
$ out/Release/node --experimental-ffi test_ffi_gc.js

No errors. Script runs to completion.

[nodejs-github-bot]

Review requested:

• @nodejs/ffi

[codecov]

Codecov Report

✅ All modified and coverable lines are covered by tests.
✅ Project coverage is 89.65%. Comparing base (8173251) to head (5d3ffc4).
⚠️ Report is 5 commits behind head on main.

Additional details and impacted files

@@            Coverage Diff             @@
##             main   #63024      +/-   ##
==========================================
- Coverage   91.49%   89.65%   -1.85%     
==========================================
  Files         358      708     +350     
  Lines      151574   220376   +68802     
  Branches    23921    42263   +18342     
==========================================
+ Hits       138679   197570   +58891     
- Misses      12619    14655    +2036     
- Partials      276     8151    +7875     

Files with missing lines	Coverage Δ
src/node_ffi.cc	69.84% <100.00%> (ø)
src/node_ffi.h	72.72% <ø> (ø)

... and 469 files with indirect coverage changes

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[nodejs-github-bot]

CI: https://ci.nodejs.org/job/node-test-pull-request/73010/

[mcollina]

lgtm