Move FakeLogBuffer to test utils

Test: run CommunalWidgetRepositoryImplTest, which depends on
FakeLogBuffer, from sysui-studio
Bug: 305308711
Fix: 305308711

Change-Id: I7952651151c7384a1972d9a315cead7beba4d82c
diff --git a/packages/SystemUI/Android.bp b/packages/SystemUI/Android.bp
index 4954cb4..9b7c80b 100644
--- a/packages/SystemUI/Android.bp
+++ b/packages/SystemUI/Android.bp
@@ -243,9 +243,6 @@
         "tests/src/com/android/systemui/statusbar/pipeline/shared/data/repository/FakeConnectivityRepository.kt",
         "tests/src/com/android/systemui/statusbar/pipeline/wifi/data/repository/FakeWifiRepository.kt",
 
-        /* Log fakes */
-        "tests/src/com/android/systemui/log/core/FakeLogBuffer.kt",
-
         /* QS fakes */
         "tests/src/com/android/systemui/qs/pipeline/domain/interactor/FakeQSTile.kt",
     ],
diff --git a/packages/SystemUI/tests/src/com/android/systemui/log/core/FakeLogBuffer.kt b/packages/SystemUI/tests/utils/src/com/android/systemui/log/core/FakeLogBuffer.kt
similarity index 100%
rename from packages/SystemUI/tests/src/com/android/systemui/log/core/FakeLogBuffer.kt
rename to packages/SystemUI/tests/utils/src/com/android/systemui/log/core/FakeLogBuffer.kt