Bug 1729413 - Upgrade the android-build docker image to Debian 11. r=taskgraph-reviewers,bhearsum

Differential Revision: https://phabricator.services.mozilla.com/D124743

taskcluster/ci/docker-image/kind.yml

@@ -174,7 +174,7 @@ jobs:
         definition: toolchain-build
     android-build:
         symbol: I(agb)
-        parent: debian10-base
+        parent: debian11-base
     fetch:
         symbol: I(fetch)
         parent: debian11-raw

taskcluster/docker/recipes/prepare_openjdk.sh

@@ -2,8 +2,9 @@
 
 set -x
 
-# Debian 10 doesn't have openjdk-8, so add the Debian 9 repository, which contains it.
-if grep -q ^10\\. /etc/debian_version; then
-	sed s/buster/stretch/ /etc/apt/sources.list | tee /etc/apt/sources.list.d/stretch.list
+# Debian >= 10 doesn't have openjdk-8, so add the Debian 9 repository, which contains it.
+version=$(awk -F. '{print $1}' /etc/debian_version)
+if test "$version" -ge 10; then
+	sed -n "s/ [^/ ]* main/ stretch main/p;q" /etc/apt/sources.list | tee /etc/apt/sources.list.d/stretch.list
 	apt-get update
 fi