Bump class-transformer from 0.2.3 to 0.3.1 (#600)

Author: dependabot[bot]

package-lock.json

@@ -49,7 +49,7 @@
     "template-url": "^1.0.0"
   },
   "peerDependencies": {
-    "class-transformer": "^0.2.3",
+    "class-transformer": "^0.3.1",
     "class-validator": "^0.12.2"
   },
   "devDependencies": {
@@ -65,7 +65,7 @@
     "chai": "^4.2.0",
     "chai-as-promised": "^7.1.1",
     "chakram": "^1.5.0",
-    "class-transformer": "^0.2.3",
+    "class-transformer": "^0.3.1",
     "class-validator": "^0.12.2",
     "copyfiles": "^2.3.0",
     "cors": "^2.8.5",