Config => Fix readonly bug

AssignmentChecker/src/config/Config.ts

@@ -13,11 +13,11 @@ class Config {
         project: string; resultsVolume: string; resultsDojo: string; resultsExercise: string;
     };
 
-    public readonly assignment!: {
+    public assignment!: {
         name: string; secret: string;
     };
 
-    public readonly dockerhub!: {
+    public dockerhub!: {
         repositories: {
             assignmentChecker: string
         }