Update ICU

Rolling v8/third_party/icu: https://chromium.googlesource.com/chromium/deps/icu/+log/fbc6faf..b9f6d0a

Add Latin-ASCII transliteration (Frank Tang)
https://chromium.googlesource.com/chromium/deps/icu/+/b9f6d0a

R=v8-waterfall-sheriff@grotations.appspotmail.com,mtv-sf-v8-sheriff@grotations.appspotmail.com,ftang@chromium.org

Change-Id: Ic00c9e3f4aa2a14a80e33f090975c73ec1169fa1
Reviewed-on: https://chromium-review.googlesource.com/c/v8/v8/+/3384678
Commit-Queue: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Bot-Commit: v8-ci-autoroll-builder <v8-ci-autoroll-builder@chops-service-accounts.iam.gserviceaccount.com>
Cr-Commit-Position: refs/heads/main@{#78596}

DEPS

@@ -228,7 +228,7 @@ deps = {
   'third_party/googletest/src':
     Var('chromium_url') + '/external/github.com/google/googletest.git' + '@' + '6b74da4757a549563d7c37c8fae3e704662a043b',
   'third_party/icu':
-    Var('chromium_url') + '/chromium/deps/icu.git' + '@' + 'fbc6faf1c2c429cd27fabe615a89f0b217aa4213',
+    Var('chromium_url') + '/chromium/deps/icu.git' + '@' + 'b9f6d0a5c5375dc4643f35360d257dba37c1d3e1',
   'third_party/instrumented_libraries':
     Var('chromium_url') + '/chromium/src/third_party/instrumented_libraries.git' + '@' + 'e09c4b66b6e87116eb190651421f1a6e2f3b9c52',
   'third_party/ittapi': {