Bump Bazel version to 3.7.0

Change-Id: I944b3376481f0d93976a0fb772124de6e758d296
diff --git a/.bazelversion b/.bazelversion
index 1545d96..7c69a55 100644
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-3.5.0
+3.7.0