Selector must be specified when From is set to "Selector". In that case,
only Routes in Namespaces matching this Selector will be selected by this
Gateway. This field is ignored for other values of "From".
matchLabels is a map of {key,value} pairs. A single {key,value} in the matchLabels
map is equivalent to an element of matchExpressions, whose key field is "key", the
operator is "In", and the values array contains only "value". The requirements are ANDed.
Selector must be specified when From is set to "Selector". In that case, only Routes in Namespaces matching this Selector will be selected by this Gateway. This field is ignored for other values of "From".