fix: support other API urls for API_ONLY apps (#234)

Author: bflorian

lib/smart-app.js

@@ -432,7 +432,13 @@ class SmartApp {
 	}
 
 	async handleOAuthCallback(request) {
-		const oauthClient = new SmartThingsOAuthClient(this._clientId, this._clientSecret, this._redirectUri)
+		const oauthClient = this._apiUrl && this._refreshUrl ?
+			new SmartThingsOAuthClient(this._clientId, this._clientSecret, this._redirectUri,
+				{
+					baseURL: this._apiUrl,
+					authURL: this._refreshUrl,
+					keyApiURL: this._authorizer._keyResolver._httpKeyResolve._keyApiHost}) :
+			new SmartThingsOAuthClient(this._clientId, this._clientSecret, this._redirectUri)
 		const auth = await oauthClient.redeemCode(request.query.code)
 		const ctx = await this.withContext({
 			installedAppId: auth.installed_app_id,