Bump Bazel version to 3.5.1

This latest release includes cherry picks, a new feature and some
important changes [1].

[1] https://github.com/bazelbuild/bazel/releases/tag/3.5.1

Change-Id: I171f5c010eb969e8dcdeb8ade358d28bddcf794d
diff --git a/jenkins-docker/slave-bazel-nocache/Makefile b/jenkins-docker/slave-bazel-nocache/Makefile
index 542ab97..fd73a31 100644
--- a/jenkins-docker/slave-bazel-nocache/Makefile
+++ b/jenkins-docker/slave-bazel-nocache/Makefile
@@ -2,7 +2,7 @@
 
 NO_CACHE=false
 IMAGE=gerritforge/gerrit-ci-slave-bazel:debian-stretch-nocache
-BAZEL_VER=3.5.0
+BAZEL_VER=3.5.1
 BUILDIFIER_VER=3.5.0
 BAZELISK_VER=1.6.1
 NODE_VER=10