[CI] Publish build scans to develocity.scala-lang.org

[adpi2]

For the Context, Gradle is supporting the Scala Center with a free instance of Develocity that we can use to analyze the build scans of our open-source projects.

This PR configures publishing of build scans for every GitHub workflow of the scala/scala3 CI. All build scans will be publicly available on https://develocity.scala-lang.org/.

The sbt-develocity plugin can also do test retry and flaky test detection, which I will activate in a subsequent PR, on some test classes.

[dotta]

@adpi2 Overall, this looks good to me. One thing I noticed is that we should add the Develocity banner in the README (I'll share an example soon). By the way, have you intentionally left out (for later) configuring the test retry functionality (for flaky test detection)?

[dotta]

@adpi2 Here is the Develocity banner that should be added to the README.

[c00ler]

Great work!

[adpi2]

The Cmd Tests action in the CI fails on:

/__w/scala3/scala3/project/scripts/../../project/scripts/sbt ';scalac tests/pos/HelloWorld.scala -d /tmp/tmp.gM6j1UN9n9 ;scalac -print-tasty -color:never /tmp/tmp.gM6j1UN9n9/HelloWorld.tasty' > /tmp/tmp.SRKPwqL5Yy
grep -qe '0: ASTs' /tmp/tmp.SRKPwqL5Yy

The TASTy tree is expected to be printed in the temporary file /tmp/tmp.SRKPwqL5Yy but it is only printed in the console.

I believe there is some sort of interaction between sbt-develocity and the build on the loggers and/or the System.out, which changes the way log messages are directed to the console or the file.

@dotta @c00ler @Duhemm can you help me with this?

[adpi2]

This is ready for review. The scans should appear automatically on develocity.scala-lang.org after we merge.

[WojciechMazur]

LGTM

[adpi2]

It is not yet ready to merge because we want to disable local and remote cache. We will re-enable it later once we agree on the rollout plan.