[clang] [Clang] Implement P2718R0 "Lifetime extension in range-based for loops" (PR #76361)

[Shafik Yaghmour via cfe-commits]

================
@@ -238,3 +239,236 @@ void init_capture_init_list() {
   // CHECK: call {{.*}}dtor
   // CHECK: }
 }
+
+namespace P2718R0 {
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shafik wrote:

Is it possible to also test the case where it does not clean up like in the proposal:

```cpp
for (auto e : f2(g())) {}  // undefined behavior
```


https://github.com/llvm/llvm-project/pull/76361