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

@@ -5272,10 +5272,14 @@ type-is@~1.6.15:
     media-typer "0.3.0"
     mime-types "~2.1.15"
 
-"typescript@>=2.0.0 <2.6.0", typescript@^2.3.3, typescript@~2.5.0:
+"typescript@>=2.0.0 <2.6.0", typescript@^2.3.3:
   version "2.5.3"
   resolved "https://registry.yarnpkg.com/typescript/-/typescript-2.5.3.tgz#df3dcdc38f3beb800d4bc322646b04a3f6ca7f0d"
 
+typescript@~2.6.1:
+  version "2.6.1"
+  resolved "https://registry.yarnpkg.com/typescript/-/typescript-2.6.1.tgz#ef39cdea27abac0b500242d6726ab90e0c846631"
+
 uglify-js@3.1.x:
   version "3.1.5"
   resolved "https://registry.yarnpkg.com/uglify-js/-/uglify-js-3.1.5.tgz#4c1a6d53b2fe77e4710dd94631853effd3ff5143"