Dereference of an explicit null value

Defect 73586 (STATIC_C)
Checker FORWARD_NULL (subcategory deref_constant_null)
File: /src/mongo/db/modules/enterprise/src/encryptdb/wiredtiger_encryption_test.cpp
Function mongo::<unnamed>::WiredTigerUtilHarnessHelper::WiredTigerUtilHarnessHelper(const std::basic_string<char, std::char_traits<char>, std::allocator<char>>&, const std::basic_string<char, std::char_traits<char>, std::allocator<char>>&)