## Is your feature request related to a problem?

You can currently install plugins from Github and NPM sources, but not GitLab

## Describe the solution you'd like

Copy a GitLab URL to install a plugin

## Describe alternatives you've considered

Using the plugin source editor.

## Additional context

Came from a conversation in the Users' slack

#### *Thank you* for your feature request – we love each and every one!

posthog/plugins/test/test_utils.py
self.assertEqual(parsed_url["pkg"], "posthog-helloworld-plugin")
        self.assertEqual(parsed_url["version"], "0.0.0")
        parsed_url = parse_url(
            "https://www.npmjs.com/package/posthog-helloworld-plugin/v/0.0.0", get_latest_if_none=True
        )
        self.assertEqual(parsed_url["type"], "npm")
        self.assertEqual(parsed_url["pkg"], "posthog-helloworld-plugin")
        self.assertEqual(parsed_url["version"], "0.0.0")
    def test_download_plugin_archive(self, mock_get):
        plugin_github_zip_1 = download_plugin_archive(
            "https://www.github.com/PostHog/helloworldplugin/commit/82c9218ee40f561b7f37a22d6b6a0ca82887ee3e",
            HELLO_WORLD_PLUGIN_GITHUB_ZIP[0],
        )
        self.assertEqual(plugin_github_zip_1, base64.b64decode(HELLO_WORLD_PLUGIN_GITHUB_ZIP[1]))
        plugin_github_zip_2 = download_plugin_archive(
            "https://www.github.com/PostHog/helloworldplugin/commit/{}".format(HELLO_WORLD_PLUGIN_GITHUB_ZIP[0])
        )
        self.assertEqual(plugin_github_zip_2, base64.b64decode(HELLO_WORLD_PLUGIN_GITHUB_ZIP[1]))
        plugin_npm_tgz = download_plugin_archive("https://www.npmjs.com/package/posthog-helloworld-plugin/v/0.0.0")
        self.assertEqual(plugin_npm_tgz, base64.b64decode(HELLO_WORLD_PLUGIN_NPM_TGZ[1]))
    def test_get_json_from_archive(self, mock_get):
        plugin_json_zip = get_json_from_archive(base64.b64decode(HELLO_WORLD_PLUGIN_GITHUB_ZIP[1]), "plugin.json")
        self.assertEqual(plugin_json_zip["name"], "helloworldplugin")
        self.assertEqual(plugin_json_zip["url"], "https://github.com/PostHog/helloworldplugin")
        self.assertEqual(plugin_json_zip["description"], "Greet the World and Foo a Bar, JS edition!")
        plugin_json_tgz = get_json_from_archive(base64.b64decode(HELLO_WORLD_PLUGIN_NPM_TGZ[1]), "plugin.json")
        self.assertEqual(plugin_json_tgz["name"], "helloworldplugin")
        self.assertEqual(plugin_json_tgz["url"], "https://github.com/PostHog/helloworldplugin")
        self.assertEqual(plugin_json_tgz["description"], "Greet the World and Foo a Bar, JS edition!")