upgrade sbt-projectmatrix to 0.7.0

Author: dwickern

project/plugins.sbt

@@ -4,5 +4,5 @@ addSbtPlugin("org.scala-js" % "sbt-scalajs" % "1.4.0")
 addSbtPlugin("org.xerial.sbt" % "sbt-sonatype" % "3.9.5")
 addSbtPlugin("com.jsuereth" % "sbt-pgp" % "2.0.2")
 addSbtPlugin("com.github.gseitz" % "sbt-release" % "1.0.13")
-addSbtPlugin("com.eed3si9n" % "sbt-projectmatrix" % "0.6.0")
+addSbtPlugin("com.eed3si9n" % "sbt-projectmatrix" % "0.7.0")
 addSbtPlugin("org.jetbrains" % "sbt-ide-settings" % "1.1.0")