src: fix race on process exit and off thread CA loading

When calling `process.exit()` or on uncaught exceptions as soon as the
process starts, the process will try to terminate immediately. In this
case, there could be a race condition on the unfinished off-thread
system CA loader which tries to access the OpenSSL API which has been
de-inited on the main thread.

Author: legendecas

src/api/environment.cc

@@ -1,4 +1,5 @@
 #include <cstdlib>
+#include "crypto/crypto_util.h"
 #include "env_properties.h"
 #include "node.h"
 #include "node_builtins.h"
@@ -1004,6 +1005,11 @@ void DefaultProcessExitHandlerInternal(Environment* env, ExitCode exit_code) {
   // in node_v8_platform-inl.h
   uv_library_shutdown();
   DisposePlatform();
+
+#if HAVE_OPENSSL
+  crypto::CleanupCachedRootCertificates();
+#endif  // HAVE_OPENSSL
+
   Exit(exit_code);
 }