fix: generating API update object schemas

backend/src/api/categories/dto/update-category.dto.ts

-import { PartialType } from '@nestjs/mapped-types';
+import { PartialType } from '@nestjs/swagger';
 import { CreateCategoryDto } from './create-category.dto';
 
 export class UpdateCategoryDto extends PartialType(CreateCategoryDto) {}

backend/src/api/directors/dto/update-director.dto.ts

-import { PartialType } from '@nestjs/mapped-types';
+import { PartialType } from '@nestjs/swagger';
 import { CreateDirectorDto } from './create-director.dto';
 
 export class UpdateDirectorDto extends PartialType(CreateDirectorDto) {}

backend/src/api/movies/dto/update-movie.dto.ts

-import { PartialType } from '@nestjs/mapped-types';
+import { PartialType } from '@nestjs/swagger';
 import { CreateMovieDto } from './create-movie.dto';
 
 export class UpdateMovieDto extends PartialType(CreateMovieDto) {}