fix(key-manager): replace deprecated link (#4451)

Author: nerda-codes

pages/key-manager/concepts.mdx

@@ -51,7 +51,7 @@ DEKs are **not stored in or managed by Key Manager**. Users are responsible for
 
 A cryptographic operation used to convert [ciphertext](#ciphertext) back into its original [plaintext](#plaintext) form, using a key encryption key.
 
-The only way to decrypt an encrypted payload is by using the `Decrypt` [endpoint](https://www.scaleway.com/en/developers/api/key-manager/V1/#path-keys-decrypt-data). Since key versions never leave Key Manager, there is no other way to decrypt data outside Key Manager.  A payload encrypted with an older key version can still be decrypted. In this case, for convenience, the payload encrypted with the latest key version will be returned, along with the decrypted payload.
+The only way to decrypt an encrypted payload is by using the `Decrypt` [endpoint](https://www.scaleway.com/en/developers/api/key-manager/#path-keys-decrypt-an-encrypted-payload). Since key versions never leave Key Manager, there is no other way to decrypt data outside Key Manager.  A payload encrypted with an older key version can still be decrypted. In this case, for convenience, the payload encrypted with the latest key version will be returned, along with the decrypted payload.
 
 ## Encryption