Migration: Exception thrown while using ODBC connections tring

[Jay Bienvenu]

I'm trying to create a migration from a local instance of SQL Server. When I test the connection, the following message appears: 'grt.Dict key must be a string'. Looking in the log, I find this message. How do I resolve this?

```
15:43:30 [ERR][ pymforms]: Unhandled exception in Python code:
Traceback (most recent call last):
File "/usr/lib/mysql-workbench/modules/migration_source_selection.py", line 226, in test_connection
if not source.connect():
File "/usr/lib/mysql-workbench/modules/migration.py", line 199, in connect
self._rev_eng_module.connect(self.connection, self.password or "")
SystemError: NotConnectedError("No open connection to Mssql@Driver=ODBC Driver 18 for SQL Server;Server=tcp:localhost,1433;UID=sa;PWD=xx"): error calling Python module function DbMssqlRE.connect

During handling of the above exception, another exception occurred:

Traceback (most recent call last):
File "/usr/lib/mysql-workbench/modules/migration_source_selection.py", line 331, in go_advanced
self.test_connection(self.main.plan.migrationSource, "Source")
File "/usr/lib/mysql-workbench/modules/migration_source_selection.py", line 256, in test_connection
username = source.connection.parameterValues.userName
KeyError: 'grt.Dict key must be a string'
```