[ENH] Upgrade Swagger Dependencies

[ThoreKr]

The restmapper pulls in a rather dated release of io.swagger:swagger-jersey2-jaxrs (Nov 2017).

There are two potential ways to fix this:

1. Upgrade to 1.6.2;
   The 1. release has seen a couple of updates (last in June 2020) and seems not to break too many things. This however could already provide a couple of improvements, mostly because jersey pulls in jackson and that version is authoritative fol all other projects. There have been a couple of CVEs, mostly with medium severity and related to potential denial of service attacks.

2. Upgrade to Swagger Core 2
   This is a larger upgrade with probable impact on other services, as endpoint annotations have to be updated, but would provide the quite noteable milestone of OpenAPI 3.0 support.

Version Rereference. https://github.com/swagger-api/swagger-core#compatibility

[pdolif]

Upgraded to version 1.6.3 (see 6325aa5).