Add a symlink for the ICU .dat file

The ICU .dat file was moved into the runtime APEX file
in commit b6d855f081c232309961f31c7c7c8a76abf79c3c.
There are some apps that know the old location and its
absence causes them to fail.

This change adds a symlink from the old directory to
the new directory. The ICU .dat file changes its name
with every ICU major release so this is simpler than
linking the file itself.

Bug: 119293618
Bug: 120853401
Bug: 122985829
Test: make droid / inspect output
Test: Confirm broken app works on an internal master build
Change-Id: I452dcb5e52975011c9ebd3db2caa621bbefedaf3