chore(deps): pin dependencies

Author: renovate-bot

package.json

@@ -32,13 +32,13 @@
     "graphql-import": "^0.4.5"
   },
   "devDependencies": {
-    "@types/jest": "^22.1.4",
-    "@types/node": "^9.4.6",
-    "ts-jest": "^22.4.1",
-    "graphql": "^0.13.1",
-    "jest": "^22.4.2",
-    "memory-fs": "^0.4.1",
-    "typescript": "^2.7.2",
-    "webpack": "^4.0.1"
+    "@types/jest": "22.2.3",
+    "@types/node": "9.6.41",
+    "ts-jest": "22.4.6",
+    "graphql": "0.13.2",
+    "jest": "22.4.4",
+    "memory-fs": "0.4.1",
+    "typescript": "2.9.2",
+    "webpack": "4.28.1"
   }
 }