Convert name to lowercase in TargetedLookup

This diff does the following.

Converts the name in DoTargetedLookup to lowercase. This makes the lookup case-insensitive which is the correct way.
Fixes lint which happen automatically when I save the file in VSCode.

Testing:

» echo "cmu.edu" | ./zdns nslookup | python -m json.tool
{
    "data": {
        "servers": [
            {
                "ipv4_addresses": [
                    "38.96.147.4"
                ],
                "name": "NY-SERVER-03.NET.CMU.EDU",
                "ttl": 19804,
                "type": "NS"
            },
            {
                "ipv4_addresses": [
                    "128.237.148.168"
                ],
                "name": "NSAUTH2.NET.CMU.EDU",
                "ttl": 19804,
                "type": "NS"
            },
            {
                "ipv4_addresses": [
                    "128.2.1.8"
                ],
                "name": "NSAUTH1.NET.CMU.EDU",
                "ttl": 19804,
                "type": "NS"
            }
        ]
    },
    "name": "cmu.edu",
    "status": "NOERROR",
    "timestamp": "2022-04-28T10:29:35-07:00"
}

» echo "NY-SERVER-03.NET.cmu.edu" | ./zdns alookup | python -m json.tool
{
    "data": {
        "ipv4_addresses": [
            "38.96.147.4"
        ]
    },
    "name": "NY-SERVER-03.NET.cmu.edu",
    "status": "NOERROR",
    "timestamp": "2022-04-28T10:29:51-07:00"
}

zmap / zdns

Convert name to lowercase in TargetedLookup #303