fix: correctly initialize exception mapping

The constructor of an exception filter must be given
an instance of HttpAdapterHost, otherwise it will crash at runtime.

This can be reproduced by GETing /.

Reference: https://docs.nestjs.com/exception-filters#inheritance
Signed-off-by: David Mehren <git@herrmehren.de>

src/errors/error-mapping.ts

@@ -6,6 +6,7 @@
 import {
   ArgumentsHost,
   BadRequestException,
+  Catch,
   ConflictException,
   InternalServerErrorException,
   NotFoundException,
@@ -67,6 +68,7 @@ const mapOfHedgeDocErrorsToHttpErrors: Map<string, HttpExceptionConstructor> =
     ],
   ]);
 
+@Catch()
 export class ErrorExceptionMapping extends BaseExceptionFilter<Error> {
   catch(error: Error, host: ArgumentsHost): void {
     super.catch(ErrorExceptionMapping.transformError(error), host);