Do not install extensions on start up when remote does not support installing extensions

[sandy081]

I see users are having remote set up with limited network connectivity. In such cases they can configure to install extensions on remote by downloading them locally enabling setting - remote.downloadExtensionsLocally. This will download extensions locally and install the downloaded extensions in the remote.

But I see dev containers and remote SSH extensions start servers on remote with passing extensions to install on start up. If remote cannot support installing extension (recently have issues with signing verifications), then this is can lead to remote not working or taking long time to start or with some bad experience.

Hence, I would recommend remote extensions not to start server with installing extensions in these situation and install the extension after starting the server via client.