fix: remove entrypoint to ensure we can pass commands as arrays instead of quoted strings

plugins/builder-railpack/dockerfiles/builder-build.Dockerfile

@@ -1,7 +1,4 @@
 ARG APP_IMAGE
 FROM $APP_IMAGE
 
-RUN printf '#!/usr/bin/env bash\nset -x\nexec bash -l -c -- \"$*\"\n' > /usr/local/bin/entrypoint && \
+ENTRYPOINT []
-    chmod +x /usr/local/bin/entrypoint
-
-ENTRYPOINT ["/usr/local/bin/entrypoint"]