style: fix linting issues met Prettier

backend/src/entities/users/student.entity.ts

@@ -4,12 +4,20 @@ import { Class } from '../classes/class.entity.js';
 import { Group } from '../assignments/group.entity.js';
 import { StudentRepository } from '../../data/users/student-repository.js';
 
-@Entity({ repository: () => {return StudentRepository} })
+@Entity({
+    repository: () => {
+        return StudentRepository;
+    },
+})
 export class Student extends User {
-    @ManyToMany(() => {return Class})
+    @ManyToMany(() => {
+        return Class;
+    })
     classes!: Collection<Class>;
 
-    @ManyToMany(() => {return Group})
+    @ManyToMany(() => {
+        return Group;
+    })
     groups!: Collection<Group>;
 
     constructor(