Always pull newest image

Signed-off-by: Jacob Kiers <jacob@jacobkiers.net>

.drone.jsonnet

@@ -16,6 +16,7 @@ local add_build_steps() = [
   {
     name: getStepName(arch),
     image: cross_image,
+    pull: true,
     volumes: [
       {
         name: 'dockersock',
@@ -48,6 +49,7 @@ local add_build_steps() = [
     [{
       name: 'Wait for Docker',
       image: cross_image,
+      pull: true,
       commands: [
         'mkdir artifacts',
         'while ! docker image ls; do sleep 1; done',
@@ -90,6 +92,7 @@ local add_build_steps() = [
   services: [{
     name: 'docker',
     image: 'docker:dind',
+    pull: true,
     privileged: true,
     volumes: [
       {