Automatic refresh error when using VSTS.Feed with a parameter

You are correct in your research - powerbi.com prevents certain modifications of queries like these.

There are some workarounds for web.contents function 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/

However i don't believe this trick works with odata as-is. You should use OData.Feed function (instead of VSTS.Feed) and then do the folding in desktop designer, i.e. start with complete /WorkItem  list like so:

OData.Feed("https://myproject.analytics.visualstudio.com/WCDProd/_odata/WorkItems?$select=WorkItemId,Title")

And then filter the column in query designer - this will add the parameter to your query programmatically and you may be able to modify it at runtime.