Switched to using constant already defined for AES-128 block sizes

Signed-off-by: Jacob Prud'homme <2160185+jacobprudhomme@users.noreply.github.com>

Author: jacobprudhomme

cryptoki/tests/basic.rs

@@ -1682,7 +1682,7 @@ fn sha256_digest_multipart_with_key() -> TestResult {
     let key_template = vec![
         Attribute::Token(true),
         Attribute::Private(false),
-        Attribute::ValueLen((256 / 8).into()),
+        Attribute::ValueLen((AES128_BLOCK_SIZE as u64).into()),
         // Key must be non-sensitive and extractable to get its bytes and digest them directly, for comparison
         Attribute::Sensitive(false),
         Attribute::Extractable(true),