refactor: make webclient response parsing more fault-tolerant

[tomwwinter]

Currently we try to parse the response from a webClient call directly within the "bodyToMono" block, wich lead to an decoding error when our DTO is not matching the response result. Also we lost here the actually response from the remote service.

Improvement:

Parse all responses as String and try to map them after that with jacksonObjectMapper. If parsing fails now, we are still able to log the actually response.