Always installs latest version of code server

[Mahesha999]

Removes hardcoded vscode version CODESERVER_VERSION. Thus, it always installs latest version of code server. With hard coded version, I was unable to install the extensions from the vscode extensions marketplace. Also it seems that ngrok now requires users to create authtoken. So, this version might need users to provide their authtoken:

ColabCode(port=80, password="<enter-password>", mount_drive=True, authtoken='<enter-your-ngrok-auth-token>`)

Sample colab notebook to boot up with colabcode.

[sb0210]

Overall Code can be improved.
output of subprocess.run command is not taken care of.
Comments can be removed.

def _install_code():
    result = subprocess.run(["wget", "https://code-server.dev/install.sh"], stdout=subprocess.PIPE)
    if result.returncode != 0:
        raise RuntimeError("Failed to download installation script")
        
    result = subprocess.run(["sh", "install.sh"], stdout=subprocess.PIPE)
    if result.returncode != 0:
        raise RuntimeError("Failed to run installation script")