Bump github.com/nats-io/nats-server/v2 from 2.9.17 to 2.9.19

Bumps [github.com/nats-io/nats-server/v2](https://github.com/nats-io/nats-server) from 2.9.17 to 2.9.19.
- [Release notes](https://github.com/nats-io/nats-server/releases)
- [Changelog](https://github.com/nats-io/nats-server/blob/main/.goreleaser.yml)
- [Commits](https://github.com/nats-io/nats-server/compare/v2.9.17...v2.9.19)

---
updated-dependencies:
- dependency-name: github.com/nats-io/nats-server/v2
  dependency-type: direct:production
  update-type: version-update:semver-patch
...

Signed-off-by: dependabot[bot] <support@github.com>

vendor/github.com/nats-io/nats-server/v2/server/ipqueue.go

@@ -104,6 +104,9 @@ func (q *ipQueue[T]) push(e T) int {
 // emptied the queue. So the caller should never assume that pop() will
 // return a slice of 1 or more, it could return `nil`.
 func (q *ipQueue[T]) pop() []T {
+	if q == nil {
+		return nil
+	}
 	var elts []T
 	q.Lock()
 	if q.pos == 0 {