The way I got around it is to just run the compose file explicitly
I had to make a change, though
```
diff --git a/docker-compose-arm64.yml b/docker-compose-arm64.yml
index 9f0f7f8..8bbd3f0 100644
--- a/docker-compose-arm64.yml
+++ b/docker-compose-arm64.yml
@@ -25,7 +25,7 @@ services:
         networks:
             - kohanet
     koha:
-        image: koha/koha-testing:${KOHA_IMAGE}
+        image: koha/koha-testing:master-bullseye-arm64v8
         depends_on:
             - db
             - es
```
which leads me to believe that the set_arch func is not invoked because I see no reason why it shouldn't work as expected.