Description of problem:
When the user uses the Web terminal operator and close it with the command `exit` the bottom panel should just disappear. Instead it shows an error.

Version-Release number of selected component (if applicable):
4.10+

Tested this on the Developer Sandbox. Might exist also on older versions.

How reproducible:
Always

Steps to Reproduce:
1. Install Web Terminal operator or test it on the OpenShift Developer sandbox.
2. Open the "Command line terminal" with the button in the main navigation
3. Type `exit`

Actual results:
The terminal closes and shows an error (red message) "The terminal connection has closed."

Expected results:
The terminal should just close if the session closes successfully / without any error.

Additional info: