⚡ Simplify property types in credentials (#1869)

packages/nodes-base/credentials/ConvertKitApi.credentials.ts

@@ -1,6 +1,6 @@
 import {
 	ICredentialType,
-	NodePropertyTypes,
+	INodeProperties,
 } from 'n8n-workflow';
 
 
@@ -8,11 +8,11 @@ export class ConvertKitApi implements ICredentialType {
 	name = 'convertKitApi';
 	displayName = 'ConvertKit API';
 	documentationUrl = 'convertKit';
-	properties = [
+	properties: INodeProperties[] = [
 		{
 			displayName: 'API Secret',
 			name: 'apiSecret',
-			type: 'string' as NodePropertyTypes,
+			type: 'string',
 			default: '',
 			typeOptions: {
 				password: true,