tasks: Fix OpenShift instances

Commit 93523ff broke OpenShift deployments: The `export HOME`
from `setup-tasks` isn't visible in the main `cockpit-tasks` loop, so
the GitHub API fails to resolve the user's home dir.

Put it back for now. This is far from elegant, but we need to unbreak
the statistics queue quickly.

tasks/cockpit-tasks

@@ -11,6 +11,11 @@ COCKPIT_BOTS_BRANCH=${COCKPIT_BOTS_BRANCH:-main}
 WORKDIR="$PWD"
 BOTS_DIR="$WORKDIR"/bots
 
+# OpenShift instances with their random user don't set $HOME
+if [ -z "${HOME}" ]; then
+    export HOME=/work
+fi
+
 echo "Starting testing"
 
 function update_bots() {