Return value of function which returns null is dereferenced without checking

Defect 98215 (STATIC_C)
Checker NULL_RETURNS (subcategory none)
File: /src/mongo/db/dbwebserver.cpp
Function mongo::<unnamed>::CommandsHandler::_cmd(const std::basic_string<char, std::char_traits<char>, std::allocator<char>>&) const
/src/mongo/db/dbwebserver.cpp, line: 292
Assigning: "cmd" = null return value from "findCommand".

            Command* cmd = Command::findCommand(cmdName);