feat(upload): inclui a propriedade url no evento upload

Esta melhoria permite a alteração da `url` no evento `upload`, assim  o
componente fica compativel com a API de upload do Fluig.

Fixes #1825

projects/ui/src/lib/components/po-field/po-upload/po-upload-base.service.ts

@@ -41,7 +41,8 @@ export class PoUploadBaseService {
     const filesLength = files.length;
     const uploadEvent: any = {
       data: {},
-      file: null
+      file: null,
+      url: url
     };
 
     for (let i = 0; i < filesLength; i++) {
@@ -57,6 +58,7 @@ export class PoUploadBaseService {
         tOnUpload.emit(uploadEvent);
 
         formData.append('data', JSON.stringify(uploadEvent.data));
+        url = uploadEvent.url;
       }
 
       this.sendFile(url, file, headers, formData, uploadCallback, successCallback, errorCallback);