linter 0.1.60


* new lint: `avoid_void_async`
* `unawaited_futures` updated to check cascades

Change-Id: I9378df6ab618c9a0e71f8a3c5b16d2543445b014
Reviewed-on: https://dart-review.googlesource.com/71386
Reviewed-by: Brian Wilkerson <brianwilkerson@google.com>
Commit-Queue: Phil Quitslund <pquitslund@google.com>
diff --git a/DEPS b/DEPS
index ff4bb79..8f5c4c4 100644
--- a/DEPS
+++ b/DEPS
@@ -95,7 +95,7 @@
   "intl_tag": "0.15.6",
   "jinja2_rev": "2222b31554f03e62600cd7e383376a7c187967a1",
   "json_rpc_2_tag": "2.0.9",
-  "linter_tag": "0.1.59",
+  "linter_tag": "0.1.60",
   "logging_tag": "0.11.3+2",
   "markdown_tag": "2.0.2",
   "matcher_tag": "0.12.3",