⚡ Add Harvest OAuth2 support (#697)

* credentials, generic functions fit to oauth2, UI elements

* ⚡ Improvements to Harvest-Node

* Update Harvest.node.ts

* ⚡ Add OAuth2 and move account id from credentials to node parameters

* ⚡ Minor improvements to Harvest-Node

Co-authored-by: Rupenieks <ru@myos,co>
Co-authored-by: ricardo <ricardoespinoza105@gmail.com>
Co-authored-by: Jan Oberhauser <jan.oberhauser@gmail.com>

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

@@ -8,13 +8,6 @@ export class HarvestApi implements ICredentialType {
 	displayName = 'Harvest API';
 	documentationUrl = 'harvest';
 	properties = [
-		{
-			displayName: 'Account ID',
-			name: 'accountId',
-			type: 'string' as NodePropertyTypes,
-			default: '',
-			description: 'Visit your account details page, and grab the Account ID. See <a href="https://help.getharvest.com/api-v2/authentication-api/authentication/authentication/">Harvest Personal Access Tokens</a>.',
-		},
 		{
 			displayName: 'Access Token',
 			name: 'accessToken',