Add Debian 12 to CI (#15895) (#15898)

This commit adds Debian 12 (Bookworm) to the
Linux JDK matrix pipeline and Compat Phase of the
exhaustive pipeline respectively.

Relates https://github.com/elastic/ingest-dev/issues/2871

(cherry picked from commit fedcf58c48)

Co-authored-by: Dimitrios Liappis <dimitrios.liappis@gmail.com>

.buildkite/linux_jdk_matrix_pipeline.yml

@@ -19,6 +19,8 @@ steps:
             value: "ubuntu-2204"
           - label: "Ubuntu 20.04"
             value: "ubuntu-2004"
+          - label: "Debian 12"
+            value: "debian-12"
           - label: "Debian 11"
             value: "debian-11"
           - label: "Debian 10"

.buildkite/scripts/common/vm-images.json

@@ -2,7 +2,7 @@
     "#comment": "This file lists all custom vm images. We use it to make decisions about randomized CI jobs.",
     "linux": {
         "ubuntu": ["ubuntu-2204", "ubuntu-2004"],
-        "debian": ["debian-11", "debian-10"],
+        "debian": ["debian-12", "debian-11", "debian-10"],
         "rhel": ["rhel-9", "rhel-8"],
         "oraclelinux": ["oraclelinux-8", "oraclelinux-7"],
         "rocky": ["rocky-linux-8"],