In testing, keep single-instance behavior, but quit if another instance if launched to avoid zombie instances on CI workers
In testing, keep single-instance behavior, but quit if another instance if launched to avoid zombie instances on CI workers

itchio/itch,itchio/itch,leafo/itchio-app,itchio/itch,itchio/itch,itchio/itchio-app,itchio/itchio-app,leafo/itchio-app,leafo/itchio-app,itchio/itchio-app,itchio/itch,itchio/itch