ci: drop Debian oldoldstable (stretch)

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.github/workflows/build.yml

@@ -480,9 +480,6 @@ jobs:
           - label: "debian-oldstable"
             image: "debian:oldstable-slim"
             type: "deb"
-          - label: "debian-oldoldstable"
-            image: "debian:oldoldstable-slim"
-            type: "deb"
           - label: "amazonlinux-2"
             image: "amazonlinux:2"
             type: "rpm"

CHANGELOG.md

@@ -15,6 +15,7 @@ _When adding new entries to the changelog, please include issue/PR numbers where
 - Improved tile import performance for point-cloud (and eventually raster) by making it multithreaded. [#818](https://github.com/koordinates/kart/pull/818)
 - Fixed a bug where Kart would require `user.name` and `user.email` to be set, even when `GIT_AUTHOR_EMAIL` and similar variables were set in the environment. [#812](https://github.com/koordinates/kart/issues/812)
 - Update native dependencies. [#820](https://github.com/koordinates/kart/pull/820)
+- Drop CI testing of Debian Stretch/oldoldstable. [#820](https://github.com/koordinates/kart/pull/820)
 
 ## 0.12.2