chore(package): update @types/supertest to version 2.0.9

Closes #173

Author: greenkeeper[bot]

package.json

@@ -158,7 +158,7 @@
     "@types/jest": "24.0.12",
     "@types/jsonwebtoken": "8.3.2",
     "@types/node": "12.0.0",
-    "@types/supertest": "2.0.7",
+    "@types/supertest": "2.0.9",
     "codelyzer": "5.0.1",
     "conventional-changelog-cli": "2.0.21",
     "conventional-commits-detector": "1.0.2",