deps: add no-strict-aliasing to ICU cflags

This commit adds -Wno-strict-aliasing to the icu_implementation target.
The motivation for this is that this flags is enabled when building with
macosx, and will make the output a little cleaner when building on
other operating systems.

PR-URL: https://github.com/nodejs/node/pull/23112


Reviewed-By: Anna Henningsen <anna@addaleax.net>
Reviewed-By: James M Snell <jasnell@gmail.com>