Add hjson wheel for web-tests presubmit support

Change-Id: I2b7c8ebec60fefd8b0d4ee6d1362ca37ae604278
Reviewed-on: https://chromium-review.googlesource.com/c/chromium/tools/depot_tools/+/6502114
Commit-Queue: Kameron Lutes <kalutes@google.com>
Reviewed-by: Yiwei Zhang <yiwzhang@google.com>

.vpython3

@@ -80,4 +80,11 @@ wheel: <
 wheel: <
   name: "infra/python/wheels/parameterized-py2_py3"
   version: "version:0.8.1"
+>
+
+# Used by:
+#   web-tests PRESUBMIT.py
+wheel: <
+  name: "infra/python/wheels/hjson-py2_py3"
+  version: "version:3.1.0"
 >