title: @Query() does not transform to DTO
body: <p>I have a controller that needs to receive data in the request query string (I can't use the body because I'm interacting with a legacy system). </p>
  
  <p>I wrote a DTO map query params to an object and I'm using a ValidationPipe to validate and transform the data to my DTO.</p>
  
  <p>So, I have this:</p>
  
  <pre><code>import { Get, Controller, Query, Post, Body, UsePipes, ValidationPipe } from '@nestjs/common';
  
  class TestDto {
    @IsNumber()
    field1: number;
    @IsBoolean()
    field2: boolean;
  }
  
  @Controller()
  export class AppController {
    constructor() {}
  
    @Get()
    @UsePipes(new ValidationPipe({ whitelist: false, transform: true}))
    root(@Query() dto: TestDto): TestDto {
      return dto;
    }
  
  }
  </code></pre>
  
  <p>All of the previous code compìles and follows the NestJS documentation, but when I call <a href="http://localhost:3000/?field1=15&amp;field2=true" rel="noreferrer">http://localhost:3000/?field1=15&amp;field2=true</a> I get this:</p>
  
  <pre><code>{
      "statusCode": 400,
      "error": "Bad Request",
      "message": [
          {
              "target": {
                  "field1": "15",
                  "field2": "true"
              },
              "value": "15",
              "property": "field1",
              "children": [],
              "constraints": {
                  "isNumber": "field1 must be a number"
              }
          },
          {
              "target": {
                  "field1": "15",
                  "field2": "true"
              },
              "value": "true",
              "property": "field2",
              "children": [],
              "constraints": {
                  "isBoolean": "field2 must be a boolean value"
              }
          }
      ]
  }
  </code></pre>
  
  <p>Both fields are valid according to the attributes but the pipe rejects the request. If I change from @IsNumber to @IsNumberString and from @IsBoolean to @IsBooleanString it validates, but I do not received the transformed data (i.e. I get a plain object instead of my DTO)</p>
  
  <p>Did anybody face something like this?</p>