Fix typo from `naive` to `naïve`

src/ownership.md

@@ -59,7 +59,7 @@ data.push(4);
 println!("{}", x);
 ```
 
-naive scope analysis would be insufficient to prevent this bug, because `data`
+naïve scope analysis would be insufficient to prevent this bug, because `data`
 does in fact live as long as we needed. However it was *changed* while we had
 a reference into it. This is why Rust requires any references to freeze the
 referent and its owners.

src/vec.md

@@ -13,7 +13,7 @@ many intrinsics *do* become stabilized elsewhere (`std::ptr` and `str::mem`
 consist of many intrinsics).
 
 Ultimately this means our implementation may not take advantage of all
-possible optimizations, though it will be by no means *naive*. We will
+possible optimizations, though it will be by no means *naïve*. We will
 definitely get into the weeds over nitty-gritty details, even
 when the problem doesn't *really* merit it.