Switch to Scala 2.13 (#4901)

frameworks/Scala/akka-http/akka-http.dockerfile

@@ -1,4 +1,4 @@
-FROM hseeberger/scala-sbt:8u181_2.12.8_1.2.8
+FROM hseeberger/scala-sbt:8u212_2.13.0_1.2.8
 
 WORKDIR /akka-http