Fix NameError when visit_error is set in visit_uri (#851)

[mohityadav8]

Description

This PR fixes a potential NameError in visit_uri() located in minecode/management/commands/run_visit.py.

Previously, the code referenced the exception variable e inside the if visit_error: block:

msg += get_error_message(e)

However, e is only defined inside the except block:

except (ConnectionError, Timeout, Exception) as e:

If _visit_router.process(uri_to_visit) returns a visit_error without raising an exception, the if visit_error: block executes while e is undefined, causing:

NameError: name 'e' is not defined

This PR resolves the issue by removing the reference to e and using visit_error directly when logging the error message.

This ensures the error logging works correctly even when no exception was raised.

Fixes #851.