Cherry-pick: ICU-22742 Fix handling of XA,XB,XC for addLikelySubtags

Upstream commit:
https://github.com/unicode-org/icu/pull/2977/commits/78502b61366731c5483e48d2e746742e5962632e
Upstream bug:
https://unicode-org.atlassian.net/browse/ICU-22742

Add more tests.
ICU-22742 Add PS... variants
ICU-22742 Add java tests
ICU-22742 extend tests
ICU-22742 wrap java

Bug: 331740612
Test: atest CtsIcuTestCases CtsIcu4cTestCases
Change-Id: I91546706f5918ac353c0bf779ba6f16c0a0a1c5d
8 files changed