Update ztApi.ts - change default URL of the Local Zerotier URL

I think address http://zerotier:9993 may be a bit misleading, especially for the standalone version installations.
My proposition is to use by default (if not specified in .env file ZT_ADDR variable) http://127.0.0.1:9993 which should work everywhere.

src/utils/ztApi.ts

@@ -38,7 +38,7 @@ if (os.platform() === "freebsd") {
 	ZT_FILE = process.env.ZT_SECRET_FILE || `${ZT_FOLDER}/authtoken.secret`;
 }
 
-const LOCAL_ZT_ADDR = process.env.ZT_ADDR || "http://zerotier:9993";
+const LOCAL_ZT_ADDR = process.env.ZT_ADDR || "http://127.0.0.1:9993";
 const CENTRAL_ZT_ADDR = "https://api.zerotier.com/api/v1";
 
 let ZT_SECRET = process.env.ZT_SECRET;