Hide JSON tab with IP addresses when BTCEXP_HIDE_IP=true

[infertux]

Even with BTCEXP_HIDE_IP=true (default config), all the IP addresses of the node are visible on the "Node Status" JSON tab. This can be seen at https://explorer.electroncash.de/node-status for instance. Even though the IPs are hidden in the "Details" tab, they are visible in the "JSON" tab.

This PR hides the "JSON" tab altogether, another approach might be to hide just the sub-tab tab-getnetworkinfo. I could edit the PR if you'd rather do that.