insert missing prefix/suffix vertical bars and improve md readability (#11350)

Signed-off-by: etgraylog <[email protected]>

Author: etgraylog

_api-reference/snapshots/create-repository.md

@@ -105,12 +105,12 @@ The `server_side_encryption` setting is removed as of OpenSearch 3.1.0. S3 appli
 
 ### hdfs repository
 
- Request field                     | Description                                                                                                  
-:----------------------------------|:-------------------------------------------------------------------------------------------------------------
-| `uri`                             | The HDFS URI of the `hdfs://<HOST>:<PORT>/path/to/backup` format. Required.                                    |
-| `path`                            | The path within HDFS where you want to store snapshots (for example, `/my/snapshot/directory`). Required. |
-| `security.principal`              | The Kerberos principal to use when connecting to HDFS. Optional.                                             |
-| `conf.<key>`                  | Additional HDFS client configuration settings (for example, `core-site.xml` or `hdfs-site.xml`). Optional.                |
+| Request field        | Description                                                                                                 |
+|:---------------------|:------------------------------------------------------------------------------------------------------------|
+| `uri`                | The HDFS URI of the `hdfs://<HOST>:<PORT>/path/to/backup` format. Required.                                 |
+| `path`               | The path within HDFS where you want to store snapshots (for example, `/my/snapshot/directory`). Required.   |
+| `security.principal` | The Kerberos principal to use when connecting to HDFS. Optional.                                            |
+| `conf.<key>`         | Additional HDFS client configuration settings (for example, `core-site.xml` or `hdfs-site.xml`). Optional.  |