add a setting key for postgres image name

src/main/scala/com/github/tototoshi/sbt/slick/PluginDBSupport.scala

@@ -15,6 +15,7 @@ trait PluginDBSupport {
   protected val startDb = taskKey[Unit]("Stop and remove the postgres container")
 
   lazy val postgresContainerPort = settingKey[Int]("The port of postgres port")
+  lazy val postgresImage = settingKey[String]("The postgres image name")
   lazy val postgresVersion = settingKey[String]("The postgres version")
 
   protected def dbSettings: Seq[sbt.Setting[_]] = {
@@ -24,6 +25,7 @@ trait PluginDBSupport {
         flywayDefaults / Keys.logLevel := Level.Warn,
         postgresDbUrl := s"jdbc:postgresql://127.0.0.1:${postgresContainerPort.value}/postgres",
         postgresContainerPort := 15432,
+        postgresImage := "postgres",
         postgresVersion := "13.7",
         flywayUrl := postgresDbUrl.value,
         flywayUser := dbUser,
@@ -35,6 +37,7 @@ trait PluginDBSupport {
               PostgresContainer.start(
                 exportPort = postgresContainerPort.value,
                 password = dbPass,
+                postgresImage = postgresImage.value,
                 postgresVersion = postgresVersion.value,
                 logger = Keys.streams.value.log
               )

src/main/scala/com/tubitv/PostgresContainer.scala

@@ -18,10 +18,10 @@ object PostgresContainer {
 
   private val runningDb = new AtomicReference[Option[String]](None)
 
-  def start(exportPort: Int, password: String, postgresVersion: String, logger: Logger): Unit = {
+  def start(exportPort: Int, password: String, postgresImage: String, postgresVersion: String, logger: Logger): Unit = {
     runningDb.get() match {
       case None =>
-        val image = s"postgres:$postgresVersion"
+        val image = s"$postgresImage:$postgresVersion"
         val dockerClient = DockerClientBuilder.getInstance.build
         Try(dockerClient.inspectImageCmd(image).exec()).recover {
           case _: NotFoundException =>