Fix .kotlin_builtins glob

The files in kotlin jars seem to be called .kotlin_builtins, not
.kotlin_builtin.

Test: m checkbuild
Change-Id: I541aea758bbef6bb23632836cceb8339b82ffdff
diff --git a/java/java.go b/java/java.go
index 89aa0e1..cf0aafd 100644
--- a/java/java.go
+++ b/java/java.go
@@ -1034,7 +1034,7 @@
 			// TODO(pszczepaniak): Support kotlin-reflect
 			stripFiles = append(stripFiles,
 				"**/*.kotlin_module",
-				"**/*.kotlin_builtin")
+				"**/*.kotlin_builtins")
 		} else {
 			// Only add kotlin-stdlib if not using (on-device) renamed stdlib
 			// (it's expected to be on device bootclasspath)