ci: replace EOL Debian bullseye with trixie in integration matrix (#222)

Debian 11 bullseye's bullseye-security apt Release file has expired on
the mirror, causing 'apt-get update' to fail (exit 100) in the echo
Dockerfile and breaking all bullseye integration jobs regardless of
Python version. Bullseye is oldstable/EOL-track; replace it with the
current stable release, trixie (Debian 13), across Python 3.10-3.14.

Author: maxday

.github/workflows/test-on-push-and-pr.yml

@@ -103,21 +103,25 @@ jobs:
             runtime_version: "3.14"
             python_location: /usr/local/bin/python
           - distro: debian
-            distro_version: bullseye
+            distro_version: trixie
             runtime_version: "3.10"
             python_location: /usr/local/bin/python
           - distro: debian
-            distro_version: bullseye
+            distro_version: trixie
             runtime_version: "3.11"
             python_location: /usr/local/bin/python
           - distro: debian
-            distro_version: bullseye
+            distro_version: trixie
             runtime_version: "3.12"
             python_location: /usr/local/bin/python
           - distro: debian
-            distro_version: bullseye
+            distro_version: trixie
             runtime_version: "3.13"
             python_location: /usr/local/bin/python
+          - distro: debian
+            distro_version: trixie
+            runtime_version: "3.14"
+            python_location: /usr/local/bin/python
           # Amazon Linux 2
           - distro: amazonlinux2
             distro_version: "2"