Clean code from GitpodServerLauncher and update JetBrains backend-plugin to work when user has proxies

[felladrin]

Description

Clean code from GitpodServerLauncher and update JetBrains backend-plugin to work when the user has proxies.

This reverts the hotfix from #11232 and passes a default SslContextFactory to HttpClient, which the root cause of the issue #11228. For reference, this is the error message the server was triggering:

java.lang.IllegalStateException: HttpClient has no SslContextFactory, wss:// URI's are not supported in this configuration
at io.gitpod.gitpodprotocol.api.GitpodServerLauncher.listen

Related Issue(s)

Resolves #11291

How to test

• Open https://felladrin-11291.preview.gitpod-dev.com/#referrer:jetbrains-gateway:intellij/https://github.com/gitpod-io/empty
• Get the instance of the workspace by running env | grep GITPOD_INSTANCE_ID
• Check if heartbeats are sent to set to the server.

Release Notes

Gitpod Plugin for JetBrains IDEs was updated to properly handle network proxies.

Documentation

None.

Werft options:

• /werft with-preview

[felladrin]

I wasn't able to run gpctl workspaces last-heartbeat command from the preview environment (as instructed in the "How to test" section), but I confirm the workspace was up for almost two hours, meaning the refactoring succeeded. So I'm setting it as Ready for Review.

[akosyakov]

i did not try, but code changes looks good.

/hold

if someone wants to test, if not please merge

[akosyakov]

I wasn't able to run gpctl workspaces last-heartbeat command

just look at logs and see what JB backend can connect to Gitpod API

[akosyakov]

/unhold