chore: update tslint (#6149)

Updates tslint to 5.5.0 and resolves some errors that weren't being caught before. This version also has the advantage of printing out the full stack trace if one of the rules throws an error.

package-lock.json

@@ -14323,9 +14323,9 @@
       "integrity": "sha1-vIAEFkaRkjp5/oN4u+s9ogF1OOw="
     },
     "tslint": {
-      "version": "5.4.3",
-      "resolved": "https://registry.npmjs.org/tslint/-/tslint-5.4.3.tgz",
-      "integrity": "sha1-dhyEArgONHt3M6BDkKdXslNYBGc=",
+      "version": "5.5.0",
+      "resolved": "https://registry.npmjs.org/tslint/-/tslint-5.5.0.tgz",
+      "integrity": "sha1-EOjas+MGH6YelELozuOYKs8gpqo=",
       "dev": true,
       "requires": {
         "babel-code-frame": "6.22.0",
@@ -14345,15 +14345,6 @@
           "resolved": "https://registry.npmjs.org/colors/-/colors-1.1.2.tgz",
           "integrity": "sha1-FopHAXVran9RoSzgyXv6KMCE7WM=",
           "dev": true
-        },
-        "tsutils": {
-          "version": "2.6.0",
-          "resolved": "https://registry.npmjs.org/tsutils/-/tsutils-2.6.0.tgz",
-          "integrity": "sha1-5emceaiszTl3zhjYP98dI1psLrs=",
-          "dev": true,
-          "requires": {
-            "tslib": "1.7.1"
-          }
         }
       }
     },