test: remove duplicated buffer negative allocation test
The buffer negative allocation test test-buffer-negative-length.js is almost duplicated with test-buffer-no-negative-allocation.js.
So remove test-buffer-negative-length.js and add SlowBuffer
allocation test into test-buffer-no-negative-allocation.js.
Checklist
-
make -j4 test
(UNIX), orvcbuild test
(Windows) passes -
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