Custom connector You can't schedule refresh for this semantic model because the following data sourc

Hello,

i created custom connector to github:

[DataSource.Kind="GitHub", Publish="GitHub.Publish"]
shared GitHub.Contents = (repositoryName as text, optional folderPath as text) =>
    let
        baseUrl = "https://api.github.com/",
        url = "repos/xxx/" & repositoryName & "/contents/" & folderPath,
        source = Json.Document(Web.Contents(baseUrl, [
            RelativePath = url,
            Headers = [
                #"Authorization" = "Bearer " & Extension.CurrentCredential()[access_token],
                #"User-Agent" = "PowerQuery"
            ]
        ]))
    in
        source;

GitHub = [
    Authentication = [
        OAuth = [
            StartLogin = (resourceUrl, state, display) =>
                let
                    authorizeUrl = "https://github.com/login/oauth/authorize?" &
                        "client_id=" & client_id &
                        "&redirect_uri=https://oauth.powerbi.com/views/oauthredirect.html" &
                        "&scope=repo" &
                        "&state=" & state
                in
                    [
                        LoginUri = authorizeUrl,
                        CallbackUri = "https://oauth.powerbi.com/views/oauthredirect.html",
                        WindowHeight = 720,
                        WindowWidth = 1024,
                        Context = null
                    ],

            FinishLogin = (context, callbackUri, state) =>
                let
                    parts = Uri.Parts(callbackUri)[Query],
                    code = parts[code],
                    access_token_response = Json.Document(Web.Contents("https://github.com/login/oauth/access_token", [
                        Content = Text.ToBinary("client_id=" & client_id & "&client_secret=" & client_secret & "&code=" & code),
                        Headers = [
                            #"Content-Type" = "application/x-www-form-urlencoded",
                            Accept = "application/json"
                        ]
                    ])),
                    access_token = access_token_response[access_token]
                in
                    [
                        access_token = access_token
                    ],

            Refresh = (resourceUrl, refresh_token) => error "GitHub does not support refresh tokens.",
            TestConnection = (access_token_record) => {"https://api.github.com/user"},
            AccessToken = (access_token_record) => "Bearer " & access_token_record[access_token]
        ]
    ]
];

GitHub.Publish = [
    Beta = true,
    Category = "Other",
    ButtonText = { Extension.LoadString("ButtonTitle"), Extension.LoadString("ButtonHelp") },
    LearnMoreUrl = "https://powerbi.microsoft.com/",
    SourceImage = GitHub.Icons,
    SourceTypeImage = GitHub.Icons
];

GitHub.Icons = [
    Icon16 = { Extension.Contents("GitHub16.png"), Extension.Contents("GitHub20.png"), Extension.Contents("GitHub24.png"), Extension.Contents("GitHub32.png") },
    Icon32 = { Extension.Contents("GitHub32.png"), Extension.Contents("GitHub40.png"), Extension.Contents("GitHub48.png"), Extension.Contents("GitHub64.png") }
];

and got in pwoer bi service: 

"You can't schedule refresh for this semantic model because the following data sources currently don't support refresh"

i used relative path in first function, what i am missing?

Sources how to fix it applied from here:
https://blog.crossjoin.co.uk/2016/08/16/using-the-relativepath-and-query-options-with-web-contents-in-power-query-and-power-bi-m-code/ 
https://www.youtube.com/watch?v=fstsQMZiHME 

Best,
Jacek