Allow localhost without adding require_tld:false

[maxgalbu]

Describe the bug
During development, I want to validate localhost as a correct URL, but to do so I need to add require_tld:false.
This forces me to make require_tld variable based on the environment, since I want to check for TLDs in production environment.

I think you should check the whitelist before checking if it's a IP or FQDN here:

validator.js/src/lib/isURL.js

Line 138 in 5b04cc5

if (!isIP(host) && !isFQDN(host, options) && (!ipv6 || !isIP(ipv6, 6))) {

I can open a Pull request if you agree!

Additional context
Validator.js version: 13.6
Node.js version: 16
OS platform: macOS

[tux-tn]

Thank you for your suggestion @maxgalbu
I agree in the fact that whitelist parameter should take precedence over isIP and isFQDN checks. Feel free to open a PR !

[deepanshu2506]

I'll work on this...