Update dotnet-file.yml with fix to create pull request action

Author: kzu

.github/workflows/dotnet-file.yml

@@ -70,7 +70,7 @@ jobs:
           validate: false
 
       - name: ✍ pull request
-        uses: peter-evans/create-pull-request@v4
+        uses: peter-evans/create-pull-request@v6
         with:
           base: main
           branch: dotnet-file-sync