Add an explicit dependency on livedata

Ensures that fragments has a direct,
explicit api dependency on livedata-core
as it is part of its public API surface.

Test: ./gradlew bOS
Change-Id: If1e17fddf4cb606a38355ef1c73c3cad4bbf5236
diff --git a/fragment/fragment/build.gradle b/fragment/fragment/build.gradle
index f85b451..1e2bc5a 100644
--- a/fragment/fragment/build.gradle
+++ b/fragment/fragment/build.gradle
@@ -25,6 +25,7 @@
     api("androidx.viewpager:viewpager:1.0.0")
     api("androidx.loader:loader:1.0.0")
     api(project(":activity:activity"))
+    api(project(":lifecycle:lifecycle-livedata-core"))
     api(project(":lifecycle:lifecycle-viewmodel"))
 
     androidTestImplementation(KOTLIN_STDLIB)