[BP of MB-54451] Backup/Restore fails when bucket name contains "." character

func filterQueryMap(filterString string, include bool) (map[string]bool, error) {

    filterMap := make(map[string]bool)

    var keyspace []rune

    escaped := false

    nDots := 0

    filterString += ","

    for _, r := range filterString {

        if escaped {

            escaped = false

        } else {

            if r == '\\' {

                escaped = true

                continue

            } else if r == ',' {

                if len(keyspace) > 0 {

                    if nDots > 2 {

                        return nil, fmt.Errorf("Malformed input filter %s", string(keyspace))

                    }

                    filterMap[string(keyspace)] = include

                    keyspace = keyspace[:0]

                    nDots = 0

                }

                continue

            } else if r == '.' {

                nDots++

            }

        }

        keyspace = append(keyspace, r)

    }

    return filterMap, nil

}