Increase test time to 900 seconds

Pull-replication integration tests can take more than 300 seconds
to execute. This cause timeout and build fail. Increase timeout
to 900 seconds.

Change-Id: I508664ce5f02fbca9719c569161d46160ce9c197
diff --git a/BUILD b/BUILD
index aad6d61..5a7d344 100644
--- a/BUILD
+++ b/BUILD
@@ -23,6 +23,7 @@
 
 junit_tests(
     name = "pull_replication_tests",
+    size = "large",
     srcs = glob([
         "src/test/java/**/*Test.java",
         "src/test/java/**/*IT.java",