Add Prout to guardian/story-packages

This is prompted by the outage caused by #184,
where new PROD instances of https://packages.gutools.co.uk/ couldn't
start up. Although more specific testing would catch this issue before
it went live, as a last resort, it's good to know that a pull request
has _not_ gone live after merging, and that's one of the things
Prout can help with - posting a 'OVERDUE' message against the PR.

See also:

* https://github.com/guardian/prout
* https://www.theguardian.com/info/developer-blog/2015/feb/03/prout-is-your-pull-request-out
* Other examples of configuring Prout:
  * guardian/mobile-apps-api#2507
  * guardian/apple-news#232

.prout.json

@@ -0,0 +1,5 @@
+{
+    "checkpoints": {
+        "PROD": { "url": "https://packages.gutools.co.uk/_healthcheck", "overdue": "20M" }
+    }
+}

app/controllers/StatusController.scala

@@ -1,11 +1,12 @@
 package controllers
 
+import app.BuildInfo
 import conf.ApplicationConfiguration
 import play.api.libs.ws.WSClient
 import play.api.mvc.ControllerComponents
 
 class StatusController(config: ApplicationConfiguration, components: ControllerComponents, wsClient: WSClient) extends StoryPackagesBaseController(config, components, wsClient) {
   def healthStatus = Action { request =>
-    Ok("Ok.")
+    Ok(s"Ok.\ngitCommitId:${BuildInfo.gitCommitId}")
   }
 }

build.sbt

@@ -1,3 +1,5 @@
+import scala.sys.env
+
 name := "story-packages"
 
 version := "1.0.0"
@@ -53,6 +55,10 @@ resolvers ++= Seq(
     Resolver.file("Local", file(Path.userHome.absolutePath + "/.ivy2/local"))(Resolver.ivyStylePatterns)
 )
 
+buildInfoPackage := "app"
+buildInfoOptions += BuildInfoOption.BuildTime
+buildInfoKeys += "gitCommitId" -> env.getOrElse("GITHUB_SHA", "Unknown")
+
 lazy val jacksonVersion = "2.13.4"
 lazy val jacksonDatabindVersion = "2.13.4.2"
 
@@ -93,4 +99,4 @@ libraryDependencies ++= jacksonOverrides ++  Seq(
     "org.scalatest" %% "scalatest" % "3.2.15" % "test"
 )
 
-lazy val root = (project in file(".")).enablePlugins(PlayScala, RiffRaffArtifact, JDebPackaging, SystemdPlugin)
+lazy val root = (project in file(".")).enablePlugins(PlayScala, RiffRaffArtifact, JDebPackaging, SystemdPlugin, BuildInfoPlugin)

project/plugins.sbt

@@ -3,12 +3,13 @@ logLevel := Level.Warn
 
 resolvers ++= Seq(
   Classpaths.typesafeReleases,
-  Resolver.sonatypeRepo("releases"),
   Resolver.typesafeRepo("releases")
-)
+) ++ Resolver.sonatypeOssRepos("releases")
 
 addSbtPlugin("com.typesafe.play" % "sbt-plugin" % "2.8.19")
 
 addSbtPlugin("com.gu" % "sbt-riffraff-artifact" % "1.1.12")
 
+addSbtPlugin("com.eed3si9n" % "sbt-buildinfo" % "0.11.0")
+
 libraryDependencies += "org.vafer" % "jdeb" % "1.3" artifacts (Artifact("jdeb", "jar", "jar"))