Notebook: error if select connection and cancel

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Open ADS and open a notebook Click select connection and open the connection dialog. Click cancel

Expected:

• Cleanly cancels out Actual:
• Get error Changing context failed: No valid connection
• Get extra Select connection in the dropdown.

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Thanks for submitting this issue. Please also check if it is already covered by an existing one, like:

• Notebooks: Clicking Cancel on Add New Connection Dialog Removes Connection (#4281)
• 'Attach to' with Spark kernel resets to sql connection on cancelling connection dialog (#4024)
• Notebooks: Ensure every provider has cancel functionality (#3719)