Revert "test: mark test_buffer/test_finalizer flaky"

This reverts commit 73d8db8.

PR-URL: #43418
Reviewed-By: Benjamin Gruenbaum <[email protected]>
Reviewed-By: Chengzhong Wu <[email protected]>
Reviewed-By: Tobias Nießen <[email protected]>
Reviewed-By: James M Snell <[email protected]>
Reviewed-By: Richard Lau <[email protected]>
Reviewed-By: Michael Dawson <[email protected]>

Author: mcollina

test/node-api/node-api.status

@@ -5,6 +5,5 @@ prefix node-api
 # sample-test                        : PASS,FLAKY
 
 [true] # This section applies to all platforms
-test_buffer/test_finalizer : PASS,FLAKY
 
 [$system==win32]