Format lib/BUILD with buildifier

Change-Id: I63db70e6e6f4da44a211621d8721ede66bce44bd
Signed-off-by: David Pursehouse <david.pursehouse@gmail.com>

lib/BUILD

@@ -172,9 +172,9 @@ java_library(
     testonly = 1,
     visibility = ["//visibility:public"],
     exports = [
-        "@mockito//jar",
         "@byte_buddy//jar",
         "@byte_buddy_agent//jar",
+        "@mockito//jar",
         "@objenesis//jar",
     ],
 )