While working on the GIt 2.29.0 update, we noticed that projections were failing to match vanilla Git when it came to the GVFlt_MoveFileTests/LongFileName folder. The root cause is that ProjFS updated recently in response to a security bug, but that fix included a change to how it handles resizing filename buffers.

With the help of @wilbaker and @cgallred, we discovered the root cause, and the ProjFS team is working on a fix.

In order to get us unblocked, we need to stop testing this scenario until ProjFS ships to the Azure Pipelines build machines.

1. Remove the GVFlt_MoveFileTests/LongFileName folder in the test repo (using new branches FunctionalTests/20201014*)
2. Point VFS for Git functional tests to that branch, and ignore any tests that care about that folder. (Fix functional tests to skip around ProjFS issue #1697)
3. Periodically check if we can revert that change to the functional tests.
4. Revert the test changes.