[resteasy-dev] New dependency on reactive-contexts

[Stephane Epardaud]

So I finally have a snapshot version of smallrye-concurrency that is 
pushed to the nexus oss snapshots, and the mpconcurrency snapshot to 
eclipse maven snapshots too, which means I can finally open a PR on 
resteasy to try out the smallrye-concurrency variant on resteasy's CI.

I will open the PR tomorrow, but it's not for merging: it's only for 
testing on the CI because there was a classloader-related bug I fixed in 
reactivecontexts that I want to make sure does not cause any issue in 
smallrye-concurrency, and I was never able reproduce it outside of the 
CI. So when you see the PR, can you please send it on its way to the CI 
and not merge it ?

Thanks!