chore: add script to force delete a namespace (#1345)

tools/force-delete-namespace.sh

@@ -0,0 +1,32 @@
+#! /bin/sh
+
+namespace="${1:?Namespace not defined}"
+
+echo -n "Force deleting a namespace can leave some resources associated to the namespace alive.\nAre you sure you want to delete the namespace \`$namespace\`? [y/N] " >&2
+
+read -r answer
+
+case "$answer" in
+  y|Y|yes|Yes)
+    echo "Deleting namespace \`$namespace\`"
+    ;;
+  n|N|no|No|"")
+    echo Abort >&2
+    exit 1
+    ;;
+  *)
+    echo "Unrecognized answer \`$answer\`: it should be either yes or no.\nAbort" >&2
+    exit 2
+    ;;
+esac
+
+kubectl delete namespaces "$namespace" --force --grace-period=0 --timeout=10s || {
+  kubectl proxy --port=1337 & pid=$!
+  sleep 1
+
+  curl -fsS "http://localhost:1337/api/v1/namespaces/$namespace" |
+    jq '.spec.finalizers = []' |
+    curl -fsS -XPUT -H 'Content-Type: application/json' "http://localhost:1337/api/v1/namespaces/$namespace/finalize" -d @-
+
+  kill $pid
+}