chore: update dependency which to v2 (#814)

Author: renovate[bot]

@commitlint/travis-cli/package.json

@@ -62,7 +62,7 @@
     "babel-preset-commitlint": "^8.2.0",
     "babel-register": "6.26.0",
     "cross-env": "6.0.3",
-    "which": "1.3.1"
+    "which": "2.0.1"
   },
   "dependencies": {
     "@commitlint/cli": "^8.3.1",

yarn.lock

@@ -11483,7 +11483,14 @@ which@1, which@^1.2.10, which@^1.2.9:
   dependencies:
     isexe "^2.0.0"
 
-[email protected], which@^1.2.14, which@^1.3.0, which@^1.3.1:
+[email protected]:
+  version "2.0.1"
+  resolved "https://registry.npmjs.org/which/-/which-2.0.1.tgz#f1cf94d07a8e571b6ff006aeb91d0300c47ef0a4"
+  integrity sha512-N7GBZOTswtB9lkQBZA4+zAXrjEIWAUOB93AvzUiudRzRxhUdLURQ7D/gAIMY1gatT/LTbmbcv8SiYazy3eYB7w==
+  dependencies:
+    isexe "^2.0.0"
+
+which@^1.2.14, which@^1.3.0, which@^1.3.1:
   version "1.3.1"
   resolved "https://registry.npmjs.org/which/-/which-1.3.1.tgz#a45043d54f5805316da8d62f9f50918d3da70b0a"
   integrity sha512-HxJdYWq1MTIQbJ3nw0cqssHoTNU267KlrDuGZ1WYlxDStUtKUhOaJmh112/TZmHxxUfuJqPXSOm7tDyas0OSIQ==