Update sbt to 1.2.8

Author: XenonAbe

build.sbt

@@ -1,8 +1,14 @@
 // forked from sbt/sbt-coffeescript https://github.com/sbt/sbt-coffeescript
-organization := "com.github.xenonabe"
-name := "sbt-coffeescript2"
-libraryDependencies ++= Seq(
-  "org.webjars.npm" % "coffeescript" % "2.3.2",
-  "org.webjars" % "mkdirp" % "0.5.0"
-)
-addSbtJsEngine("1.2.3")
+ThisBuild / organization := "com.github.xenonabe"
+ThisBuild / name := "sbt-coffeescript2"
+ThisBuild / scalaVersion := "2.12.13"
+
+lazy val root = (project in file("."))
+  .enablePlugins(SbtPlugin)
+  .settings(
+    addSbtJsEngine("1.2.3"),
+    libraryDependencies ++= Seq(
+      "org.webjars.npm" % "coffeescript" % "2.3.2",
+      "org.webjars" % "mkdirp" % "0.5.0"
+    )
+  )

project/build.properties

@@ -1 +1 @@
-sbt.version=1.0.2
+sbt.version=1.2.8

project/plugins.sbt

@@ -1 +1 @@
-addSbtPlugin("com.typesafe.sbt" % "sbt-web-build-base" % "1.2.0")
+addSbtPlugin("com.typesafe.sbt" % "sbt-web-build-base" % "1.2.3")

version.sbt

@@ -1 +1 @@
-version in ThisBuild := "2.0.2-SNAPSHOT"
+ThisBuild / version := "2.0.2-SNAPSHOT"