Crossbuild to sbt 2.0.0 + Scala 3

[BillyAutrey]

Description
sbt 2.0.0-M2 is available, so we can start cross-building this to 2.0 and add scala3 support.

Reproducer

• Set your sbt version to 2.0.0-M2
• Add sbt-sonatype to your plugin list.
• sbt compile

[error] Error downloading org.xerial.sbt:sbt-sonatype;sbtVersion=1.0;scalaVersion=3:3.11.3
[error]   Not found
[error]   Not found
[error]   not found: https://repo1.maven.org/maven2/org/xerial/sbt/sbt-sonatype_3_1.0/3.11.3/sbt-sonatype-3.11.3.pom

[BillyAutrey]

Looks like @xuwei-k is working on this already, has a commit as recent as 10 hours ago in https://github.com/xuwei-k/sbt-sonatype/tree/wip-sbt-2

[xuwei-k]

• feature: sbt 2 support #526

[xerial]

Released https://github.com/xerial/sbt-sonatype/releases/tag/v3.12.0