Remove third party test dependencies

[yinzara]

The github.com/gin-gonic/gin dependency has a http response splitting vulnerability in versions less than 1.7.0:
gin-gonic/gin#2632

Upgrading the dependency to 1.7.0 or higher will fix this vulnerability (current version is 1.7.1)

[nhooyr]

Hi @yinzara we don't actually use gin anywhere other than in tests but I'll be sure to do this in the next release.

[nhooyr]

And apologies for the delayed response.

[jmichalak-fluxninja]

@nhooyr Any update on this? Github alerts me with GHSA-h395-qcrw-5vmq

[nhooyr]

Soon, my plan is to just move the third party tests to a different module. See #318 (comment)