fix src-dep-plugin

sbt-app/src/sbt-test/compiler-project/src-dep-plugin/build.sbt

@@ -1,5 +1,6 @@
-import Configurations.{CompilerPlugin => CPlugin}
-
-lazy val use = project.dependsOn(RootProject(file("def")) % CPlugin).settings(
-	autoCompilerPlugins := true
-)
+lazy val use = project
+  .dependsOn(RootProject(file("def")) % Configurations.CompilerPlugin)
+  .settings(
+    scalaVersion := "2.12.17",
+    autoCompilerPlugins := true
+  )

sbt-app/src/sbt-test/compiler-project/src-dep-plugin/def/build.sbt

@@ -4,6 +4,7 @@ name := "demo-compiler-plugin"
 
 version := "0.1"
 
+scalaVersion := "2.12.17"
 libraryDependencies += "org.scala-lang" % "scala-compiler" % scalaVersion.value % "provided"
 
 exportJars := true