unsafe attribute error with Rust edition 2024

[muse254]

Describe the bug

Issue building with Rust edition 2024.

The error log:

error: unsafe attribute used without unsafe
  --> /redacted/flipper/lib.rs:6:5
   |
6  | /     /// Defines the storage of your contract.
7  | |     /// Add new fields to the below struct in order
8  | |     /// to add new static storage fields to your contract.
9  | |     #[ink(storage)]
...  |
12 | |         value: bool,
13 | |     }
   | |_____^ usage of unsafe attribute
   |
help: wrap the attribute in `unsafe(...)`
   |
6  ~     unsafe(/// Defines the storage of your contract.
7  |     /// Add new fields to the below struct in order
...
12 |         value: bool,
13 ~     })
   |

error: could not compile `flipper` (bin "flipper") due to 1 previous error
ERROR: 

To Reproduce
Steps to reproduce the behavior:

1. Create the flipper contract example: cargo contract new flipper
2. In the Cargo.toml change [package.edition] to "2024". The default here was "2021".
3. Build: cargo contract build

Expected behavior

Having a more intuitive error from the cargo-contract tooling would help if the edition it's not yet supported.

Screenshots
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Environment (please complete the following information):

• OS: MacOS M1
• cargo-contract version: 5.0.3-unknown-aarch64-apple-darwin
• ink! version: 5.1.1

Additional context
Add any other context about the problem here.