This changes the DataFlowStack library so that we don't depend on our own modifications to the shared dataflow library.

This has caused us quite a lot of pain in the past. Hopefully we can avoid doing such modifications in t he future.

Commit-by-commit review recommended:

• The first commit gets rid of the Microsoft modifications to the GitHub dataflow files. It turns out that we have resolved merge conflicts incorrect for some languages for almost 6 months. So many of the files were actually very very old that wasn't being kept up-to-date with the latest developments on the GitHub side 😅 Hopefully we should only have clean merges from now on!
• The second commit autoformats the DataFlowStack library to make the diff of the last file smaller
• The last commit does the actual refactoring. Sadly, I had to duplicate some of the code to handle both taint-tracking and dataflow configurations. We can revisit this in the future.