Unable to Set Initial Database via JDBC Connection String Parameters

### Describe the bug, including details regarding any error messages, version, and platform.

When trying to set the initial/default database using the JDBC connection string for Arrow Flight SQL. It appears that none of the following connection string formats successfully set the initial database context:

* `jdbc:arrow-flight-sql://localhost:50051/databse`
* `jdbc:arrow-flight-sql://localhost:50051?database=db`
* `jdbc:arrow-flight-sql://localhost:50051?schema=db`

**Environment:**
* **Arrow Flight SQL JDBC Driver Version:** [Please specify the version you are using, 17.0.0（java 8） and 21.0.0]
* **Server Version:** Doris 2.1.8
* **Operating System:** openSUSE 15.6

No source file or test is named. Start by reproducing the issue with the three JDBC URLs against the stated Doris 2.1.8 environment and inspect how the Arrow Flight SQL JDBC driver handles connection parameters. Done means a supported connection-string form selects the requested initial database, or the limitation is documented with a clear error.

Written by the indexing model from the issue text.