Merge pull request #39180 from Zhuzhenghao/certificate-signing-requests

Make layout prettier in certificate-signing-requests.md

content/en/docs/reference/access-authn-authz/certificate-signing-requests.md

@@ -238,7 +238,11 @@ Some points to note:
 - `usages` has to be '`client auth`'
 - `expirationSeconds` could be made longer (i.e. `864000` for ten days) or shorter (i.e. `3600` for one hour)
 - `request` is the base64 encoded value of the CSR file content.
-  You can get the content using this command: ```cat myuser.csr | base64 | tr -d "\n"```
+  You can get the content using this command: 
+
+  ```shell
+  cat myuser.csr | base64 | tr -d "\n"
+  ```
 
 ### Approve certificate signing request