Merge branch 'stable-3.1' into master

* stable-3.1:
  Bump Bazel version to 3.7.0
  Upgrade bazlets to latest stable-3.0 to build with 3.0.13 API

Change-Id: I361a459ffaa2d0f90dd9fa7330669d47fb087754

WORKSPACE

diff --git a/WORKSPACE b/WORKSPACE
index 2218eff..289a582 100644
--- a/WORKSPACE
+++ b/WORKSPACE
@@ -3,7 +3,7 @@
 load("//:bazlets.bzl", "load_bazlets")
 
 load_bazlets(
-    commit = "3f9dadc615dc4053369a42d9ada37dafd8d4763c",
+    commit = "0f81174e3d1b892a1342ebc75bb4bbb158ae0efe",
     #local_path = "/home/<user>/projects/bazlets",
 )