doc: unify import order in CCM example

Refs: nodejs/node#39043

PR-URL: nodejs/node#42394
Reviewed-By: Rich Trott <rtrott@gmail.com>
Reviewed-By: Richard Lau <rlau@redhat.com>
Reviewed-By: Mestery <mestery@protonmail.com>
Reviewed-By: Luigi Pinca <luigipinca@gmail.com>
Reviewed-By: Colin Ihrig <cjihrig@gmail.com>
Reviewed-By: Akhil Marsonya <akhil.marsonya27@gmail.com>
Reviewed-By: Darshan Sen <raisinten@gmail.com>

doc/api/crypto.md

@@ -5546,12 +5546,12 @@ console.log(receivedPlaintext);
 ```
 
 ```cjs
+const { Buffer } = require('buffer');
 const {
   createCipheriv,
   createDecipheriv,
   randomBytes,
 } = require('crypto');
-const { Buffer } = require('buffer');
 
 const key = 'keykeykeykeykeykeykeykey';
 const nonce = randomBytes(12);