added array for infra and accreditation

Author: Hitansh159

models/department.js

@@ -4,16 +4,16 @@ const departmentSchema = {
   name: { type: Number, required: true },
   acronym: { type: String, required: true, immutable: true },
   yearOfStarting: { type: Date, immutable: true, required: true },
-  accreditations: {
+  accreditations: [{
     type: connector.Schema.Types.ObjectId,
     ref: 'Accreditation',
     required: true,
-  },
-  infrastructures: {
+  }],
+  infrastructures: [{
     type: connector.Schema.Types.ObjectId,
     ref: 'Infrastructure',
     required: true,
-  },
+  }],
 };
 
 const Department = connector.model('Department', departmentSchema);