geoip_updater.php fails against BIG-IP 15.x

I tested on my updated pull request which takes a list of F5s in the F5S env variable rather than changing the script.

Connecting to server [REDACTED] - (Server 1 of 1)... PHP Warning:  ssh2_connect(): Error starting up SSH connection(-5): Unable to exchange encryption keys in [REDACTED]/Vendor_code/F5/geoip_updater.php on line 131
