Merge pull request sangria-graphql#399 from scala-steward/update/sbt-protoc-1.0.8

Update sbt-protoc to 1.0.8

Author: sh0hei

project/plugins.sbt

@@ -4,5 +4,5 @@ addSbtPlugin("org.scalameta" % "sbt-scalafmt" % "2.5.4")
 addSbtPlugin("io.spray" % "sbt-revolver" % "0.10.0")
 
 // https://github.com/scalapb/ScalaPB
-addSbtPlugin("com.thesamet" % "sbt-protoc" % "1.0.7")
+addSbtPlugin("com.thesamet" % "sbt-protoc" % "1.0.8")
 libraryDependencies += "com.thesamet.scalapb" %% "compilerplugin" % "0.11.17"