slugbuilder download from minio fails

[Aaron Schlesinger]

here's the output from slugbuilder after a git push:

ENG000656:builder aaronschlesinger$ kd logs -f deis-slugbuilder
+ app_dir=/app
+ build_root=/tmp/build
+ cache_root=/tmp/cache
+ buildpack_root=/tmp/buildpacks
+ mkdir -p /app
+ mkdir -p /tmp/cache
+ mkdir -p /tmp/buildpacks
+ mkdir -p /tmp/build/.profile.d
+ [[ -z http://10.3.0.93:9000/git/home/rococo-seashore:git-4bad1ffa/tar ]]
+ [[ -e /var/run/secrets/object/store/access-key-id ]]
+ [[ -e /var/run/secrets/object/store/access-secret-key ]]
++ cat /var/run/secrets/object/store/access-key-id
+ keyID=8TZRY2JRWMPT6UMXR6I5
++ cat /var/run/secrets/object/store/access-secret-key
+ secretKey=gbstrOvotMMcg2sMfGUhA5a6Et/EI5ALtIHsobYk
++ awk -F/ '{print $3}'
++ echo http://10.3.0.93:9000/git/home/rococo-seashore:git-4bad1ffa/tar
+ domain=10.3.0.93:9000
+ echo 8TZRY2JRWMPT6UMXR6I5 gbstrOvotMMcg2sMfGUhA5a6Et/EI5ALtIHsobYk 10.3.0.93:9000
+ mc --quiet config host add 10.3.0.93:9000 8TZRY2JRWMPT6UMXR6I5 gbstrOvotMMcg2sMfGUhA5a6Et/EI5ALtIHsobYk
8TZRY2JRWMPT6UMXR6I5 gbstrOvotMMcg2sMfGUhA5a6Et/EI5ALtIHsobYk 10.3.0.93:9000
mc: Configuration written to [/app/.mc/config.json]. Please update your access credentials.
Added host ‘10.3.0.93:9000’ successfully.
+ mc --quiet cp http://10.3.0.93:9000/git/home/rococo-seashore:git-4bad1ffa/tar /tmp/slug.tgz
mc: <ERROR> Unable to stat source ‘http://10.3.0.93:9000/git/home/rococo-seashore:git-4bad1ffa/tar’. 400 Bad Request