Fix validation on links

src/links/link.dto.ts

 import { ApiModelProperty, ApiModelPropertyOptional } from '@nestjs/swagger';
+import { IsOptional, IsString, MaxLength } from 'class-validator';
 
 export class Link {
 
   @ApiModelPropertyOptional()
+  @IsOptional()
+  @MaxLength(100)
+  @IsString()
   name?: string;
 
   @ApiModelProperty()
+  @MaxLength(300)
+  @IsString()
   url: string;
 
 }
\ No newline at end of file

src/links/link.entity.ts

@@ -22,7 +22,6 @@ export class LinkEntity {
   url: string;
 
   @Column({ nullable: true })
-  @IsOptional()
   @ApiModelProperty()
   organizationId: number;