test: fix test-linux-perf flakiness

The new V8 seems to be optimizing the functions we use in this test
faster than before. Increasing the sampling frequency for Linux perf
fixes the issue.

PR-URL: #27615
Refs: v8/v8@7.4.288.21...7.4.288.27
Reviewed-By: Michaël Zasso <targos@protonmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Franziska Hinkelmann <franziska.hinkelmann@gmail.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>

Author: mmarchini

test/v8-updates/test-linux-perf.js

@@ -24,7 +24,7 @@ if (process.config.variables.node_shared)
 
 const perfArgs = [
   'record',
-  '-F500',
+  '-F999',
   '-g',
   '--',
   process.execPath,