Add ClickHouse in the database group (#3011)

semantic_conventions/trace/database.yaml

@@ -157,6 +157,9 @@ groups:
             - id: opensearch
               value: 'opensearch'
               brief: 'OpenSearch'
+            - id: clickhouse
+              value: 'clickhouse'
+              brief: 'ClickHouse'
       - id: connection_string
         tag: connection-level
         type: string

specification/trace/semantic_conventions/database.md

@@ -116,6 +116,7 @@ Some database systems may allow a connection to switch to a different `db.user`,
 | `memcached` | Memcached |
 | `cockroachdb` | CockroachDB |
 | `opensearch` | OpenSearch |
+| `clickhouse` | ClickHouse |
 <!-- endsemconv -->
 
 ### Notes and well-known identifiers for `db.system`