[jb] Update the terminal widget tab when the Gitpod Task title changes

[felladrin]

Description

This PR changes two behaviors in JetBrains IDEs:

• Update the terminal widget tab when the Gitpod Task title changes.
• Disconnect the terminal widget when Gitpod Task exits.

Related Issue(s)

• Fixes [JetBrains Backend Plugin] Update the Terminal Widget title whenever there's a change on the title from Gitpod Task Terminal #12142
• Touches [JetBrains] Task should be stopped when closing terminal tab #12126 - This doesn't fix it but alleviates it because typing "exit" in a Gitpod Task Terminal now disconnects the terminal, so users aren't able to type anything else on it. [1][2]

How to test

1. Open the Preview Environment of this PR.
2. Open any JetBrains IDE with some workspace that contains tasks defined in .gitpod.yml (e.g. https://github.com/gitpod-io/spring-petclinic)
3. Observe the terminal tab titles changing with time (while tasks finish running, or when you start "htop" on them, for example).
4. Type "exit" in a terminal that is running a Gitpod Task and confirm it shows the message "Remote terminal closed".
   

Release Notes

Terminal tabs running Gitpod Tasks now have their title updated to reflect what's currently running on it.

Werft options:

• /werft with-preview

[andreafalzetti]

I tested but prev env often times out when I choose IntelliJ and it even broke.. It's down right now, so I will try with:

/werft run with-clean-slate-deployment

👍 started the job as gitpod-build-felladrin-jetbrains-task-should-12126.5
(with .werft/ from main)

[felladrin]

Let me confirm if the loadbalancer is still up for this PrevEnv.

[felladrin]

It worked fined when using Spring PetClinic, so I've updated the description suggesting using it.

I took the chance to rebase the code on main branch. It's ready for review again.

[andreafalzetti]

works as expected!

Code LGTM. Nice work @felladrin! 🍪