Fix Query with no key parse

[ili101]

Description of the Change

Fix #1065

[ili101]

Test was falsely passing as apparently:

$c = [System.Collections.Specialized.NameValueCollection]::new()
$c    $c.Add($null, 'blue')
# Key is ""

Is not the same as:

$c = [System.Web.HttpUtility]::ParseQueryString('?blue')
# Key is $null

Get-PodeCount was filtering '?blue' but not '?blue&foo=bar' which was not consistent, now it will not filter $null keys.

[Badgerati]

LGTM! :)