Upgrade guice multibindings to match version used by Gerrit.

Package JSR305 annotation, because closure-templates depends on it but
Gerrit doesn't package it anymore, as it was replaced by own class, not
to interfere with J2EE containers, in [1].

[1] https://gerrit-review.googlesource.com/50112

Change-Id: I8f5fbdff0c45d3fc36e11314b27d83ae3f157a36
diff --git a/BUCK b/BUCK
index cbc1bb8..6ea33e4 100644
--- a/BUCK
+++ b/BUCK
@@ -74,8 +74,8 @@
 
 maven_jar(
   name = 'guice-multibindings',
-  id = 'com.google.inject.extensions:guice-multibindings:4.0-beta',
-  sha1 = '558a3dcfd203db33a5a96a70a18076c866723ee4',
+  id = 'com.google.inject.extensions:guice-multibindings:4.0-beta5',
+  sha1 = 'f432356db0a167127ffe4a7921238d7205b12682',
   license = 'Apache2.0',
   exclude_java_sources = True,
   exclude = [