docs: Just re-ordering the sidebar. (#9392)

### Description

This sidebar section is meant to convey the order in which you'd build a
Turborepo. Maybe just me, but I feel like Upgrading should always be
last.

### Testing Instructions

👀

docs/repo-docs/crafting-your-repository/meta.json

@@ -10,7 +10,7 @@
     "developing-applications",
     "using-environment-variables",
     "constructing-ci",
-    "upgrading",
-    "understanding-your-repository"
+    "understanding-your-repository",
+    "upgrading"
   ]
 }