style: fix comment formatting in RustCrypto cipher tests

Apply cargo fmt formatting to correct comment spacing from double space
to single space after // in the clippy allow attribute:

- `#[allow(clippy::unwrap_used)]  // Allow unwrap...`
+ `#[allow(clippy::unwrap_used)] // Allow unwrap...`

This ensures consistent formatting according to Rust style guidelines
and passes `cargo fmt --check` validation.

Author: rusty1968

platform/impls/rustcrypto/src/cipher.rs

@@ -367,7 +367,7 @@ impl CipherStatus for AesCtrContext {
 }
 
 #[cfg(test)]
-#[allow(clippy::unwrap_used)]  // Allow unwrap in tests for cleaner test code
+#[allow(clippy::unwrap_used)] // Allow unwrap in tests for cleaner test code
 mod tests {
     use super::*;
     use openprot_hal_blocking::cipher::BlockAligned;