repl: give repl entries unique names

This is a workaround for the REPL for a problem when multiple of the
entries have the same source text

Fixes: https://github.com/nodejs/node/issues/1337
Refs: https://bugs.chromium.org/p/v8/issues/detail?id=10284

PR-URL: https://github.com/nodejs/node/pull/34372


Reviewed-By: Ruben Bridgewater <ruben@bridgewater.de>
Reviewed-By: Anto Aravinth <anto.aravinth.cse@gmail.com>