workaround dotty issue

Author: tpolecat

test-framework/scalatest/src/test/scala/com/dimafeng/testcontainers/integration/GenericContainerSpec.scala

@@ -6,6 +6,7 @@ import com.dimafeng.testcontainers.{ForAllTestContainer, GenericContainer}
 import org.scalatest.flatspec.AnyFlatSpec
 import org.testcontainers.containers.wait.strategy.Wait
 import org.testcontainers.images.builder.ImageFromDockerfile
+import org.testcontainers.images.builder.traits.ClasspathTrait;
 
 import scala.io.Source
 
@@ -23,7 +24,8 @@ class GenericContainerSpec extends AnyFlatSpec with ForAllTestContainer {
 }
 
 class GenericContainerDockerFileSpec extends GenericContainerSpec {
-  private val imageFromDockerfile = new ImageFromDockerfile().withFileFromClasspath("Dockerfile", "generic-container-dockerfile")
+  // we can't do this in Scala 3 due to https://github.com/lampepfl/dotty/issues/12586 so this is delegated to a small Java class.
+  private val imageFromDockerfile = new JavaStub().imageFromDockerFileWithFileFromClasspath("Dockerfile", "generic-container-dockerfile")
   override val container: GenericContainer = GenericContainer(imageFromDockerfile,
     exposedPorts = Seq(80),
     waitStrategy = Wait.forHttp("/")