Task: Manage subscribers in ConvertKit

n8n workflow JSON:
{"id":"25","name":"Add subscriber to form, create tag and subscriber to the tag","nodes":[{"name":"On clicking 'execute'","type":"n8n-nodes-base.manualTrigger","position":[300,300],"parameters":{},"typeVersion":1},{"name":"ConvertKit","type":"n8n-nodes-base.convertKit","position":[500,300],"parameters":{"id":1657198,"email":"","additionalFields":{}},"credentials":{"convertKitApi":"convertkit"},"typeVersion":1},{"name":"ConvertKit1","type":"n8n-nodes-base.convertKit","position":[710,300],"parameters":{"name":"","resource":"tag"},"credentials":{"convertKitApi":"convertkit"},"typeVersion":1},{"name":"ConvertKit2","type":"n8n-nodes-base.convertKit","position":[910,300],"parameters":{"email":"={{$node[\"ConvertKit\"].json[\"subscriber\"][\"email_address\"]}}","tagId":1850395,"resource":"tagSubscriber","operation":"add","additionalFields":{"fields":{"field":[]}}},"credentials":{"convertKitApi":"convertkit"},"typeVersion":1}],"active":false,"settings":{},"connections":{"ConvertKit":{"main":[[{"node":"ConvertKit1","type":"main","index":0}]]},"ConvertKit1":{"main":[[{"node":"ConvertKit2","type":"main","index":0}]]},"On clicking 'execute'":{"main":[[{"node":"ConvertKit","type":"main","index":0}]]}}}