Remove all BUCK files

ReactAndroid/src/main/java/com/facebook/jni/BUCK

@@ -1,17 +0,0 @@
-include_defs('//ReactAndroid/DEFS')
-
-android_library(
-  name = 'jni',
-  srcs = glob(['**/*.java']),
-  deps = [
-    react_native_dep('java/com/facebook/proguard/annotations:annotations'),
-    react_native_dep('libraries/soloader/java/com/facebook/soloader:soloader'),
-  ],
-  visibility = [
-    'PUBLIC',
-  ],
-)
-
-project_config(
-  src_target = ':jni',
-)