QuarkusNative now depends on Docker while building from Gradle?
This is kinda of a question more than a bug report or something.
I was able to successfully try to use quarkus `0.13.1` to build a sample application, but what I found strange is that even though I have set (as I did in `0.12.0`) the `GRAALVM_HOME` variable, now it is using docker to build the application.

Is there an option to disable the need of using docker to build the native binary?
diff --git a/devtools/gradle/src/main/java/io/quarkus/gradle/tasks/QuarkusNative.java b/devtools/gradle/src/main/java/io/quarkus/gradle/tasks/QuarkusNative.java
index 8ec05064312..b8d0ade47a1 100644
--- a/devtools/gradle/src/main/java/io/quarkus/gradle/tasks/QuarkusNative.java
+++ b/devtools/gradle/src/main/java/io/quarkus/gradle/tasks/QuarkusNative.java
@@ -56,7 +56,7 @@ public class QuarkusNative extends QuarkusTask {
 
     private String nativeImageXmx;
 
-    private String containerRuntime = "docker";
+    private String containerRuntime;
 
     private String containerRuntimeOptions;
 
['devtools/gradle/src/main/java/io/quarkus/gradle/tasks/QuarkusNative.java']