Fix Secure Supply Chain Analysis Warning in PR pipeline (#414)

* remove package sources

* remove NuGet.config

* add .sscignore for cfs0011

* change sscignore

* add CFS0013 to sscignore

---------

Co-authored-by: Sayan Shaw <sayanshaw@microsoft.com>

.sscignore

@@ -0,0 +1,3 @@
+{
+    "cfs": ["CFS0011", "CFS0013"]
+}

test/NuGet.config

@@ -1,10 +0,0 @@
-<?xml version="1.0" encoding="utf-8"?>
-<configuration>
-  <solution>
-    <add key="disableSourceControlIntegration" value="true" />
-  </solution>
-  <packageSources>
-    <clear />
-    <add key="NuGet Official" value="https://api.nuget.org/v3/index.json" />
-  </packageSources>
-</configuration>