docs: change jsdelivr links in README.md

Author: pencilnav

README.md

@@ -1,5 +1,5 @@
 <h1 align="center">
-  <a href="http://atlasos.net"><img src="https://cdn.jsdelivr.net/gh/Atlas-OS/Atlas@main/img/banner.png" alt="Atlas" width="900" style="border-radius: 30px"></a>
+  <a href="http://atlasos.net"><img src="https://gcore.jsdelivr.net/gh/Atlas-OS/Atlas@main/img/banner.png" alt="Atlas" width="900" style="border-radius: 30px"></a>
 </h1>
   <p align="center">
     <a href="https://github.com/Atlas-OS/Atlas/blob/main/LICENSE">