Stop Debugging doesn't cause the host task to stop

[v-ruizh]

OS: Win10
Build Version: 20200513.5

Repro Steps:

1. Open a function project in VS Code.
2. Debug it, then stop debugging immediately.

Expect:
The host task is stopped.

Actual:
Stop Debugging doesn't cause the host task to stop.

[ejizba]

I see how this is annoying, but going to close as "wont-fix" for a variety of reasons:

1. There's risk involved if we add custom logic to stop tasks. VS Code or the func cli or something doesn't handle it well and we run into problems like VS Code instance freezes after terminating vscode debugging session on javascript HttpTrigger function #1401
2. There's an easy workaround - users can click the trash can icon to stop the task
3. We're consistent with standard VS Code behavior here. For example, if I do "Launch Extension (webpack)" from our repo, the webpack task (which takes an annoyingly long time) keeps going even if I stop debugging. I have to stop it manually. In that sense this issue could even be "upstream" instead of "wont fix"