src: remove icuDataDir from node config

icuDataDir seems to be redundant as it is not used anywhere.
Hence removing it.

PR-URL: https://github.com/nodejs/node/pull/24780


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: Steven R Loomis <srloomis@us.ibm.com>
Reviewed-By: Joyee Cheung <joyeec9h3@gmail.com>