fail to exit js debug session with `integratedTerminal` mode

Bug Description:

when I start a new js debug session with integratedTerminal mode, when the js process exits, there is still a debug session in the THREADS widget

Steps to Reproduce:

1. add a new js debug configuration
2. because the default console is internalConsole, we should add "console": "integratedTerminal" to the config
3. create a simple js file which could only contains a single console log line
4. start the debug session until the js file is exited
5. you can notice there is a session remains in the THREADS widget
6. you need to manually stop the remaining session to clean it

Additional Information

• Operating System: ubuntu
• Theia Version: 1.13.0
• js-debug plugin version: 1.49.8