Task: Get multiple clients' data from Invoice Ninja

n8n workflow JSON:
{"nodes":[{"name":"On clicking 'execute'","type":"n8n-nodes-base.manualTrigger","position":[220,310],"parameters":{},"typeVersion":1},{"name":"Invoice Ninja","type":"n8n-nodes-base.invoiceNinja","position":[410,310],"parameters":{"options":{},"operation":"getAll"},"credentials":{"invoiceNinjaApi":"invoice_ninja_creds"},"typeVersion":1}],"connections":{"On clicking 'execute'":{"main":[[{"node":"Invoice Ninja","type":"main","index":0}]]}}}