Merge branch 'stable-5.7'

* stable-5.7:
  Bump Bazel version to 3.1.0

Change-Id: I108815577a5aab605891496c17d6f225d35f7346
Signed-off-by: Matthias Sohn <matthias.sohn@sap.com>
diff --git a/.bazelversion b/.bazelversion
index 4a36342..fd2a018 100644
--- a/.bazelversion
+++ b/.bazelversion
@@ -1 +1 @@
-3.0.0
+3.1.0