Bump Bazel version to 3.4.1

Change-Id: I44b2f4ef809ed94d0a8c98cb524c4815be5e18f0

.bazelversion

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