Remove the community build section

Author: anatoliykmetyuk

docs/blog/_posts/2021-02-17-scala3-rc1.md

@@ -214,13 +214,6 @@ They make perfect entry points into hacking on the compiler.
 
 We are looking forward to having you join the team of contributors.
 
-## Library authors: Join our community build
-
-Scala 3 now has a set of widely-used community libraries that are built against every nightly Scala 3
-snapshot. Currently, this includes shapeless, ScalaPB, algebra, scalatest, scopt, squants and many others.
-Join our [community build](https://github.com/lampepfl/dotty/tree/master/community-build)
-to make sure that our regression suite includes your library.
-
 [Scastie]: https://scastie.scala-lang.org/?target=dotty
 
 [@odersky]: https://github.com/odersky