Workaround SBT regression to avoid an empty-named JAR entry

Author: retronym

build.sbt

@@ -290,6 +290,9 @@ lazy val commonSettings = instanceSettings ++ clearSourceAndResourceDirectories
   packageOptions in Compile in packageBin := Seq.empty,
   packageOptions in Compile in packageSrc := Seq.empty,
 
+  // workaround for SBT regression. Real fix coming in https://github.com/scala/scala/pull/8525.
+  mappings in Compile in packageBin := (mappings in Compile in packageBin).value.filterNot(_._2 == ""),
+
   // Lets us CTRL-C partest without exiting SBT entirely
   cancelable in Global := true,