deps: disable V8 concurrent sparkplug compilation

It introduces process hangs on some platforms because Node.js doesn't
tear down V8 correctly.
Disable it while we work on a solution.

Refs: nodejs#47297
Refs: https://bugs.chromium.org/p/v8/issues/detail?id=13902
PR-URL: nodejs#47450
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Yagiz Nizipli <yagiz@nizipli.com>
Reviewed-By: Michael Dawson <midawson@redhat.com>
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: James M Snell <jasnell@gmail.com>

deps/v8/src/flags/flag-definitions.h

@@ -761,7 +761,7 @@ DEFINE_BOOL(baseline_batch_compilation, true, "batch compile Sparkplug code")
 DEFINE_BOOL_READONLY(concurrent_sparkplug, false,
                      "compile Sparkplug code in a background thread")
 #else
-DEFINE_BOOL(concurrent_sparkplug, ENABLE_SPARKPLUG_BY_DEFAULT,
+DEFINE_BOOL(concurrent_sparkplug, false,
             "compile Sparkplug code in a background thread")
 DEFINE_WEAK_IMPLICATION(future, concurrent_sparkplug)
 DEFINE_NEG_IMPLICATION(predictable, concurrent_sparkplug)