Add Develocity integration

[marko-bekhta]

So that we could also publish build scans for Reactive, as we do for other projects.

For how it's done in ORM, see:

https://github.com/hibernate/hibernate-orm/blob/da2de1edc99712ffae395133532b1cd8ac49877f/gradle/gradle-develocity.gradle#L46C1-L70

For GH actions, we would need to split the build/report workflows as it's done for e.g. ORM:
https://github.com/hibernate/hibernate-orm/blob/da2de1edc99712ffae395133532b1cd8ac49877f/.github/workflows/ci.yml#L311
https://github.com/hibernate/hibernate-orm/blob/da2de1edc99712ffae395133532b1cd8ac49877f/.github/workflows/ci-report.yml#L1