Remove line

[mkurz]

After upgrading to Akka 2.6.16 we can remove following line because then scala-java8-compat will be upgraded, see akka/akka#30375:

play-ws/build.sbt

Lines 102 to 103 in eceb4ae

	// Akka brings in 0.9.0, but we want 1.0.0:
	libraryDependencySchemes += "org.scala-lang.modules" %% "scala-java8-compat" % "always",