Simply add the -k switch somewhere before the url.
Disclaimer: Use this at your own risk.
man curl | less +/--insecure
-k, --insecure
(TLS) By default, every SSL connection curl makes is verified to be secure. This option allows curl to proceed and operate
even for server connections otherwise considered insecure.
The server connection is verified by making sure the server's certificate contains the right name and verifies successfully
using the cert store.
See this online resource for further details:
https://curl.haxx.se/docs/sslcerts.html
See also --proxy-insecure and --cacert
