Bump Bazel version to 3.5.0

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

[1] https://github.com/bazelbuild/bazel/releases/tag/3.5.0

Change-Id: Ibffc2f8e0900eee74409b94d7d9e0e69f8ebe33f

.bazelversion

diff --git a/.bazelversion b/.bazelversion
index 47b322c..1545d96 100644
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-3.4.1
+3.5.0