gopls: suggest filing an issue if the user manually restarts the server

[stamblerre]

Copied from upstream: microsoft/vscode-go#3128.

[stamblerre]

#34 resolves part of this, but there is still more work:

• Suggesting an issue on restart is off by default until gopls reaches v1.0
• The gopls log should be suggested as part of the issue report
• The server should have the default behavior of restarting 5x per languageClient

[hyangah]

@stamblerre please review and update the todo list. Since we enabled the gopls by default already, we may want to ask users to file an issue when they manually restart or turn off gopls.

[stamblerre]

I think we should still wait until 1.0 to enable the issue report for a manual restart--at least until we have support for multi-module workspaces. I imagine there might be some glitches with multiple workspace folders. Do we want to ask users to file an issue right away when they turn off gopls, or should we just let the new logic that checks the value of the useLanguageServer setting take care of it?

[hyangah]

I guess, (without any evidence or data backing up), asking users to file an issue when they turn off gopls is better than asking them in the future - users would remember and explain why. And for a large project, if a maintainer decided to turn off gopls and checked in the workspace setting, nagging other contributors to turn back on doesn't make sense.