Bump Bazel version to 3.4.1

Change-Id: I23fb40dbb988a34d911c79f1354f00cae4f848a0
diff --git a/.bazelversion b/.bazelversion
index fd2a018..47b322c 100644
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-3.1.0
+3.4.1