chore: release api7ee-runtime 1.2.13 with apisix-nginx-module 1.19.9

[AlinsRan]

Picks up apisix_stream_metrics_zone, $stream_session_reason and $stream_listen_addr from api7/apisix-nginx-module#123, which the gateway's new stream Prometheus metrics are built on.

Bumping VERSION triggers the api7ee-runtime release, so this must not merge before that PR is merged and tagged 1.19.9. Draft until then.

Companion PR for the apisix-runtime line: #478

[coderabbitai]

Important

Review skipped

Auto reviews are disabled on base/target branches other than the default branch.

Please check the settings in the CodeRabbit UI or the .coderabbit.yaml file in this repository. To trigger a single review, invoke the @coderabbitai review command.

⚙️ Run configuration

Configuration used: Organization UI

Review profile: CHILL

Plan: Pro

Run ID: 31e81932-dc73-4e68-9888-3db7605c7702

You can disable this status message by setting the reviews.review_status to false in the CodeRabbit configuration file.

Use the checkbox below for a quick retry:

• 🔍 Trigger review

---

_{Comment @coderabbitai help to get the list of available commands.}