Merge pull request git-for-windows#372: ci: run Scalar functional tests for PRs against features/*

I'm running PRs pointing at `features/sparse-index` but I also want the Scalar functional tests to run for those PRs.

Author: derrickstolee

.github/workflows/scalar-functional-tests.yml

@@ -10,7 +10,7 @@ on:
   push:
     branches: [ vfs-* ]
   pull_request:
-    branches: [ vfs-* ]
+    branches: [ vfs-*, features/* ]
 
 jobs:
   scalar: