chore: update typescript to version ~2.6.1

Author: renovate[bot]

package.json

@@ -47,6 +47,6 @@
     "protractor": "~5.2.0",
     "ts-node": "~3.3.0",
     "tslint": "~5.8.0",
-    "typescript": "~2.5.0"
+    "typescript": "~2.6.1"
   }
 }

yarn.lock

@@ -5552,10 +5552,6 @@ typedarray@^0.0.6:
   version "0.0.6"
   resolved "https://registry.yarnpkg.com/typedarray/-/typedarray-0.0.6.tgz#867ac74e3864187b1d3d47d996a78ec5c8830777"
 
-typescript@~2.5.0:
-  version "2.5.3"
-  resolved "https://registry.yarnpkg.com/typescript/-/typescript-2.5.3.tgz#df3dcdc38f3beb800d4bc322646b04a3f6ca7f0d"
-
 typescript@~2.6.1:
   version "2.6.2"
   resolved "https://registry.yarnpkg.com/typescript/-/typescript-2.6.2.tgz#3c5b6fd7f6de0914269027f03c0946758f7673a4"