curl: (60) SSL certificate problem: unable to get local issuer certificate
More details here: https://curl.haxx.se/docs/sslcerts.html
So curl fails to access sites over https, even if ca-certificates is installed in your Docker container? You need to force a certificate rehash. Why this is not done by default escapes me.
/usr/bin/c_rehash
curl should be happy now. Enjoy!