added optional dbName in header for tls (#641)

* added optional dbName in header for tls

* addressed review comment

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Co-authored-by: Manish Kuri <mkuri@salesforce.com>

server/src/milvus/milvus.service.ts

@@ -37,6 +37,7 @@ export class MilvusService {
         username,
         password,
         logLevel: process.env.ATTU_LOG_LEVEL || 'info',
+        database: database || this.DEFAULT_DATABASE,
       };
 
       if (process.env.ROOT_CERT_PATH) {