Auto merge of #119892 - joboet:libs_use_assert_unchecked, r=Nilstrieb,cuviper

Use `assert_unchecked` instead of `assume` intrinsic in the standard library

Now that a public wrapper for the `assume` intrinsic exists, we can use it in the standard library.

CC #119131

library/alloc/src/vec/mod.rs

@@ -1996,7 +1996,7 @@ impl<T, A: Allocator> Vec<T, A> {
         } else {
             unsafe {
                 self.len -= 1;
-                core::intrinsics::assume(self.len < self.capacity());
+                core::hint::assert_unchecked(self.len < self.capacity());
                 Some(ptr::read(self.as_ptr().add(self.len())))
             }
         }