[RFE] add gear icon to hosts view for quick config.json access

[DumpySquare]

I commonly find that I need to look at the raw json config for vscode, which also holds the f5Hosts. It would be nice to add a quick button on the hosts view to quickly and easily have access the raw vscode config file. This would best be one with a "gear" icon

[DumpySquare]

completed for pending v3.4.0 release

commands.executeCommand('workbench.action.openSettingsJson');