PrepareBundleAsync just marks one existing file as pendingDelete

Before #119 the tool was just adding packages to a submission. Result is that now some of my apps have 4/5 packages.

Yesterday did a new release of one of those app with those many packages and my expectation was that it will clean up all obsolete packages with the fix in #119 . Unfortunately that didn't happen.

This morning I debugged what is going on

https://github.com/microsoft/msstore-cli/blob/be96083b324d3475381f093ad237d63a6ab53c82/MSStore.CLI/Helpers/IStorePackagedAPIExtensions.cs#L666-L687

The foreach is over new package files, that the tool have to upload. In my case this is one file. The package list in L668 contains 4 files.
Due to the FirstOrDefault it will only pick one existing file and mark that as pendingDelete. And since there is just one file upload it wont repeat this.

Question is, is this intended behavior or should we change the FirstOrDefault to a where with a foreach loop over the result?

Start in MSStore.CLI/Helpers/IStorePackagedAPIExtensions.cs around lines 666-687 and trace PrepareBundleAsync, focusing on the loop over new package files and the package list lookup. Confirm whether every obsolete package should be marked pendingDelete when only one new package is uploaded. Done means the intended cleanup behavior is established and the issue is resolved or documented accordingly.