report: fix recent coverity warning

Fix warning about dereferencing null env

Signed-off-by: Michael Dawson <mdawson@devrus.com>

Author: mhdawson

src/node_report.cc

@@ -857,9 +857,11 @@ std::string TriggerNodeReport(Isolate* isolate,
   // Determine the required report filename. In order of priority:
   //   1) supplied on API 2) configured on startup 3) default generated
   if (!name.empty()) {
-    THROW_IF_INSUFFICIENT_PERMISSIONS(
-        env, permission::PermissionScope::kFileSystemWrite, name, name);
-    // Filename was specified as API parameter.
+    if (env != nullptr) {
+      THROW_IF_INSUFFICIENT_PERMISSIONS(
+          env, permission::PermissionScope::kFileSystemWrite, name, name);
+      // Filename was specified as API parameter.
+    }
     filename = name;
   } else {
     std::string report_filename;