This commit attempts to turn compilation warnings into errors for node's
source code.

The motivation for this is to enable these errors to be reported by CI
runs on pull requests and be able to fix them before they land.

Currently, the following warning is generated from the inspector
protocol:
/out/Release/obj/gen/src/node/inspector/protocol/Protocol.cpp:
In member function
‘virtual std::unique_ptr<node::inspector::protocol::Value>
    node::inspector::protocol::ListValue::clone() const’:
/out/Release/obj/gen/src/node/inspector/protocol/Protocol.cpp:739:21:
error: redundant move in return statement [-Werror=redundant-move]
  739 |     return std::move(result);
      |            ~~~~~~~~~^~~~~~~~

This commit removes the move for DictionaryValue and ListValue.

This commit adds a configuration time flag named error-on-warn:
$ ./configure --help | grep -A1 error-on-warn
  --error-on-warn       Turn compiler warnings into errors for node core
                        sources.

The motivation for this is that CI jobs can use this flag to turn
warnings into errors.