Is it secure to store OAuth credentials in query?

Hi Community,

I'm developing an application that get's data from a REST API which uses OAuth2.

This query is used to get an initial access token:

= Json.Document(Web.Contents(url,[Headers = [#"Content-Type"="application/x-www-form-urlencoded",#"Authorization"="Basic BASE64(Client_Id and Secret)"],
      Content = Text.ToBinary(
           "grant_type=client_credentials"
            )
        ]
))

The Client_Id and Secret is stored BASE64 encoded inside of the actual query.

My question is if users would be able to access this information from an app published to powerbi.com?

Users will not have Edit permission on the report.

Thanks in advance!