Fix entrypoint

Turns out I wasn't that far off.

naev-macos/Dockerfile

@@ -71,7 +71,6 @@ FROM registry.fedoraproject.org/fedora-minimal:latest
 WORKDIR /
 COPY --from=build /usr/lib/osxcross /usr/lib/osxcross 
 COPY --from=build /usr/local/bin/dmg /usr/bin
-# Copy Entrypoint
 COPY macports-configure.sh /usr/bin
 
 LABEL org.opencontainers.image.authors "Naev Dev Team"
@@ -111,3 +110,6 @@ RUN microdnf --nodocs --setopt=install_weak_deps=0 -y install clang cmake gettex
 # Set WORKDIR when you spin up the image.
     mkdir -p /tmp/naevBuild
 WORKDIR /tmp/naevBuild
+
+ENTRYPOINT [ "/usr/bin/macports-configure.sh" ]
+CMD [ "/bin/bash" ]

naev-macos/macports-configure.sh

@@ -1,4 +1,4 @@
-#!/usr/bin/env bash
+#!/bin/sh
 
 # Set HOST and MACOSX_DEPLOYMENT_TARGET depending on which BUILD_ARCH is selected.
 # Also configure the macports directory for the right libraries since we build for two different targets.
@@ -22,3 +22,5 @@ else
     rm -f /usr/lib/osxcross/macports
     ln -s /usr/lib/osxcross/macports.x86_64 /usr/lib/osxcross/macports
 fi
+
+exec "$@"