fix opcode link

Author: jrakibi

decoding/welcome.mdx

@@ -30,7 +30,7 @@ Explore the core modules of Decoding Bitcoin:
 <QuickLink
     title="Scripts"
     icon="scripts"
-    href="/decoding/3-2-overview-opcodes"
+    href="/decoding/overview"
     description="Explore bitcoin scripts, their structure, and how they define the conditions for transactions."
 ></QuickLink>