[geo-ip] Crashes when mmdb files are not configured

[LaurenceJJones]

Currently the calls to lookup the IP in geoip causes a crash if they are not configured.

If they are not configured the module should just bypass and return an empty data.

cs-haproxy-spoa-bouncer/internal/api/root.go

Lines 330 to 349 in 01a7154

	"get:geo:iso": {
	handle: func(_ apiPermission.ApiPermission, args ...string) (interface{}, error) {
	if err := ArgsCheck(args, 1, 1); err != nil {
	return nil, err
	}
	log.Infof("Checking IP %s", args[0])
	val := net.ParseIP(args[0])
	if val == nil {
	return nil, fmt.Errorf("invalid IP")
	}
	record, err := a.GeoDatabase.GetCity(&val)
	if err != nil && !errors.Is(err, geo.NotValidConfig) {
	return nil, err
	}
	return geo.GetIsoCodeFromRecord(record), nil
	},

The above code should call geoDatabase.isValid() as a pre-flight check.