Fix code scanning alert no. 14: Inefficient regular expression (#40)

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Author: tacxou

src/core/filestorage/_dto/filestorage.dto.ts

@@ -33,7 +33,7 @@ export class FilestorageCreateDto extends CustomFieldsDto {
   @IsString()
   @IsNotEmpty()
   @ApiProperty({ type: String, default: '/' })
-  @Matches(/^\/(\.?[^\/\0]+\/?)+$/, { message: 'Path must be a valid path' })
+  @Matches(/^\/(?:\.?[^\/\0]+\/?)+$/, { message: 'Path must be a valid path' })
   public path: string;
 
   @IsOptional()